Jewelers classify natural diamonds according to many characteristics, determining quality by color, transparency, chromaticity, quality of cut, compliance with proportions...
But the size of a diamond, its weight, is the main decisive parameter that determines the cost of one carat. Carat big diamond significantly more expensive than a carat small stone the same quality.
The basis for the valuation of diamonds is Tavernier's rule.
Tavernier rule
The total value of a diamond is equal to the carat mass (weight) of the stone times the base price of a one-carat diamond. Thus, the price of a diamond increases exponentially from the total weight of the stone.
Comparative description of diamond appraisal systems
Absolutely all existing diamond grading systems are based on the description and assessment of four main criteria for precious stones (system 4C):
- weight (carat)
- color
- purity (Clarity)
- shape and quality of cut (Cut)
The differences between diamond grading systems lie in the way in which these criteria are assessed.
It is important to understand how subjective criteria are assessed, namely color, clarity and cut quality. Especially how the color of a diamond is assessed.
Below are comparative tables of evaluation criteria between foreign systems and the Russian system.
Today, the following diamond grading systems are most widely used in the world:
- GIA
- IDC or HRD(Higher Diamond Council of Belgium)
- Scan D.N.(Scandinavian Nomenclature)
- CIBJO(International Confederation of Jewellery, Pearls and Silver)
A comparative analysis of these systems shows that they are quite similar to each other.
As a rule, the difference in grading a diamond for color and clarity only appears in the definitions of these characteristics, while the ranges are almost the same.
Transfer from one system to another is carried out using tables.
The cleanliness rating system deserves special attention IDC, which involves measuring the size of inclusions and brightness with adjusting the purity group according to a special table.
Thus, the IDC diamond grading system can be considered more objective compared to other grading systems.
The main emphasis is on the international diamond grading system GIA and the Russian grading system.
Foreign diamond grading systems, with rare exceptions, are easily converted from one to another. However, all these systems cannot be unambiguously translated into the Russian diamond grading system and vice versa.
Since it is difficult to determine whether a surface defect is also internal, the IDC system provides for an adjustment of the clarity grade for diamonds that have noticeable surface defects. This may result in some stones being graded differently by different systems. However, the proximity of these systems to each other allows, knowing one of them, to use assessment reports made in other systems. The growing authority of the GIA system has made the system internationally famous. In particular, the GIA color grading terminology has virtually replaced traditional terminology. When comparing domestic and foreign assessment systems, the GIA system is usually chosen from the latter. Differences appear both in the principles underlying the assessment and in specific parameters and ranges.
Diamond Color Grading
According to GOST and TU current in Russia, color assessment is carried out differently for small (up to 0.29 carats) stones with a Kr-17, Kr-57 cut and for the rest (from 0.30 carats) with a Kr-57 cut. At the same time, the verbal description of different diamond color groups given in GOST is of great importance, and standards have a very limited distribution.
The terms used in GOST (for example, “color”, “color”, “shade”, “slight shade”, as well as “barely perceptible”, “very faintly colored”, “clearly visible”) allow for different interpretations, therefore they are subjective and not accurate. This is why gemologists often evaluate the color of diamonds based only on the description, which gives very low repeatability of results. According to the Russian grading system, a small diamond weighing up to 0.29 carats, for example, color group 5, is more saturated than a diamond of color group 5, but weighing from 0.30 carats.
When grading a color using the GIA system from D to Z, hue does not matter, only hue and saturation are taken into account. The color group does not depend on the size of the stone at all, and a special separate color rating system has been developed for fancy color diamonds.
Compared to the previously existing TU GOSTR 52913-2008, new subgroups within 6, 8 and 9 color groups have been added. This brings Russian color groups closer to their foreign counterparts. In particular, the yellow color standards 8-1, 8-2, 8-3 are close to the color standards K, L, M (GIA), respectively.
In Russia, based on the analysis of a large number of diamonds, several tables of the ratio of color ranges according to GOST and GIA have been developed, which are similar in content, but are acceptable and are not used in evaluation for all stones, since, starting with the appearance of a clearly visible shade of color, GOST assumes a division standards for the yellow and brown series, which is not in the American GIA rating system.
Classification of diamonds by color groups in the GIA system
| color designation | color | |
| Blue White | D | bluish-transparent |
| Ice White | E | transparent |
| Fine White | F | with a subtle tint |
| Fine White | G | grayish white |
| Top Commercial White | H | white with a subtle tint of yellow |
| Commercial White | I | |
| Top Silver | J | white with barely noticeable yellowing |
| K | white with barely noticeable yellowing | |
| Silver Cape | L | pale yellowish tint |
| Light Cape | M | slightly yellowish tint |
| N | yellowish tint | |
| Cape | O | yellow tint |
| P | yellow tint | |
| Dark Cape | Q | obvious yellow tint |
| S-Z | rich yellow color | |
Approximate correspondence of diamond color characteristics according to GOSTR 52913-2008 (Russia) and the international system GIA(Gemological Institute of America)
| GOST small up to 0.29 carats |
Kr-17 | 1 | 2 | 3 | 4 | ||||||
| Kr-57 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | ||||
| GOST medium and large from 0.30 carats |
Kr-57 | 1 | 2 | 3 | 4 | 5 | 6, 6 (1) | 7 | 8 (1-5) | 9 (1-4) | |
| GIA | D | E | F | G | H | I | J | K-Z | |||
Diamond clarity rating
The basis for assessing purity according to GIA and GOST, as well as when assessing color, is based on several different principles.
The GIA system for grading diamond clarity is based on the following principle: how difficult or easy it is for an averagely trained gemologist to detect inclusions with the naked eye or with a magnifying glass, and whether these inclusions can affect the integrity of the stone.
The basis for assessing purity according to the Russian system is the principle of describing the ratio of the number, size, nature and location of inclusions for each purity group, and there is also the concept of transparency when viewing the bottom edges through the top edges.
As when assessing the color of a diamond, the number of clarity groups is different for small and large stones, as well as for Kr-17 cut diamonds.
A comparison of diamond clarity groups for both systems is given in the conversion tables, however, as for color, it is not applicable for all stones.
To illustrate the exceptions that arise during translation, consider a diamond (0.30 carat) whose defining defect is a microseam that is difficult to detect with a magnifying glass. Such a diamond will be classified as clarity group 6 according to GOST and VS1 or VS2 according to the GIA system. When assessing the clarity of a diamond according to GOST, if a dark defect is classified as a dot, the diamond is classified as purity group 3, and if it is an inclusion, it is classified into group 6.
When assessing the clarity of a diamond using the American GIA system, the determining factors are not the nature or type of inclusions, but their size, position and relief.
Assessing the quality of a diamond cut
The current standards for precious stones in Russia are developed for the production of diamonds, and not for their expert evaluation.
That is why GOST introduced tolerances for the parameters of diamonds, according to which diamonds can correspond to different cut groups (A, B, C, D) or be outside the standard.
Strictly speaking, a diamond that does not meet GOST is not subject to evaluation.
The GIA system allows you to evaluate the quality of cut of any diamond using three composite criteria:
- proportions
- symmetry
- polishing
Classification of diamonds by clarity groups in the GIA system
| designation | cleanliness group | ||
| F | Flawless (flawlessly clean) | When observed through a 10x magnifying glass, no visible defects are observed | |
| IF | INTERNALLY FLAWLESS (pure) | At 10x magnification, internal imperfections are not noticeable, only minor surface defects are detected, which can be easily eliminated with re-polishing. | |
| VVS1 | VERY, VERY SMALL INCLUSIONS (barely noticeable inclusions) |  |
At 10x magnification, the smallest dots in VVS1 class stones are extremely difficult to see through the platform, they can only be detected when viewing the stone through the pavilion. This class also includes diamonds with very small and shallow inclusions, which are removed by repeated polishing. In VVS2 grade diamonds, the smallest inclusions can be very difficult to detect when viewing the stone through the platform. |
| VVS2 |  |
||
| VS1 | VERY SMALL INCLUSIONS (smallest inclusions) |  |
At 10x magnification, minor inclusions in the form of very small feathers and clouds are difficult to detect in VS1 grade diamonds and somewhat easier to detect in VS2 grade diamonds. |
| VS2 |  |
||
| SI1 | SMALL INCLUSIONS (small defects) |  |
small noticeable inclusions At 10x magnification, noticeable inclusions in SI1 diamonds are easily detected and very easily in SI2 diamonds. Sometimes small inclusions in SI2 clarity diamonds are visible to the naked eye. |
| SI2 |  |
||
| I1 I2 I3 | IMPERFECT (there are explicit inclusions) |  |
In diamonds of these clarity groups, obvious inclusions are visible at 10x magnification and even with the naked eye through the platform. These inclusions affect the durability of the gemstone and are so numerous that they seriously affect the clarity and brilliance of the diamond. |
GIA(Gemological Institute of America)
| characteristics of purity group | cleanliness group | ||||
|---|---|---|---|---|---|
| central zone | middle zone | peripheral zone | large and medium less than 0.30 carats |
small more than 0.29 carats |
|
| without internal and external defects | 1 | 1 | |||
| one tiny defect in the form of a bright point, visible only when viewing the diamond from the pavilion side | - | - | 2 | 2 | |
| - | no more than two tiny defects in the form of light dots | 2 | 2 | ||
| - | one tiny defect in the form of a strip | 2 | 2 | ||
| no more than three small defects in the form of light inclusions | - | - | 3 (VVS 2) | 3 (VVS) | |
| - | 3 (VVS 2) | 3 (VVS) | |||
| - | no more than two small defects in the form of a stripe | 3 (VVS 2) | 3 (VVS) | ||
| no more than two small defects in the form of dark inclusions | - | - | 4 (VVS 2) | 3 (VVS) | |
| no more than four minor defects in the form of light inclusions | 4 (VVS 2) | 3 (VVS) | |||
| no more than two minor defects in the form of stripes | 4 (VVS2) | 3 (VV 2) | |||
| no more than one minor defect in the form of a stripe and three minor defects in the form of light inclusions | 4 (VVS 2) | 3 (VVS) | |||
| - | - | 4 (VVS 2) | 3 (VVS) | ||
| one minor defect in the form of a light cloud | - | - | 5 (VS 1) | 4 (VS) | |
| one minor defect in the form of a crack | - | - | 5 (VS 1) | 4 (VS) | |
| - | - | no more than three minor defects in the form of a crack | 5 (VS 1) | 4 (VS) | |
| no more than three minor defects in the form of dark inclusions | - | - | 5 (VS 2) | 4 (VS) | |
| no more than six minor defects in the form of light inclusions and stripes | 5 (VS 2) | 4 (VS) | |||
| no more than eight small scattered defects in the form of light inclusions, stripes, cracks, transparent volumetric inclusions | 6 (VS 2) | 5 (VS) | |||
| up to five minor defects in the form of dark inclusions | 6 (SI 1) | 5 (SI 1) | |||
| one minor defect in the form of a volumetric dark inclusion | 6 (SI 1) | 5 (SI 1) | |||
| no more than eight small scattered defects in the form of light and dark inclusions, stripes, cracks, clouds, transparent volumetric inclusions | 7 (SI 1) | 5 (SI 1) | |||
| one small defect in the form of a dark inclusion | 7 (SI 1) | 5 (SI 1) | |||
| no more than two small defects in the form of dark inclusions | 7a (SI 2) | 5 (SI 2) | |||
| no more than two small defects in the form of cracks | 7a (SI 2) | 5 (SI 2) | |||
| no more than one small cloud-like defect combined with a small dark inclusion | 7a (SI 3) | 5 (SI 3) | |||
| several small defects in the form of cracks combined with a small dark inclusion | 7a (SI 3) | 5 (SI 3) | |||
| numerous small defects in the form of various inclusions and cracks | 8 (SI 3) | 6(SI 3) | |||
| one big crack | 8 (I 1) | 6(I 1) | |||
| numerous large defects in the form of various inclusions and cracks | 9 (I 1) | 6(I 1) | |||
| numerous large defects in the form of various inclusions in combination with cracks | 9 (I 2) | 6 (I 2) | |||
| numerous very large defects various types and at least 60% of the diamond's pavilion facets are transparent for viewing | 10 (I 2) | 7 (I 2) | |||
| numerous very large defects of various types and transparent to view from 60% to 30% of the diamond pavilion facets | 11 (I 3) | 8 (I 3) | |||
| numerous very large defects of various types and less than 30% of the diamond's pavilion facets are transparent to view | 12 (I 3) | 9 (I 3) | |||
Approximate correspondence between the clarity characteristics of diamonds according to GOSTR 52913-2008 (Russia) and the international system GIA
| GOST small up to 0.29 carats |
Kr-17 | 1 | 2 | 3 | 4 | 5 | 6 | |||||||
| Kr-57 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |||||
| GOST medium and large from 0.30 carats |
Kr-57 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 7a | 8 | 9 | 10 | 11 | 12 |
| GIA | F IF VVS1 VVS2 | VS1 | VS2 | SI1 | SI2 | SI3 | I1 | I2 | I3 | |||||
Today, there are several diamond grading systems in the world. Moreover, the most stringent of them are the Russian Specifications (the so-called “Technical Conditions”) and the GIA (the evaluation system of the Gemological Institute of America). Each of them has its own advantages (in the Russian one there is only one - a more strict assessment of color), but the GIA system is more advanced, since it reflects such important cut characteristics as the quality of polishing, symmetry and the presence or absence of fluorescence, which in Russian certificates never reflected. Moreover, diamonds are sold for export only with a GIA grade, while in Russian market fall with the characteristics of the specifications, since the Russian consumer is not so sophisticated.
Color.
Diamonds are distinguished by color shades - from colorless to yellow-brown. To determine the color of a diamond, the stone is compared to a color standard of the same size, after which it is assigned the appropriate color group. In accordance with the international GIA system, color shades are characterized by letter designations from D - colorless to Z - deep yellow or brown. The domestic TU scale provides designation with numbers from 1 (colorless) to 9 (brown). The color scale is divided into groups, it begins with colorless diamonds, then there are smooth transitions with increasing yellow color saturation, and ends with the last group, which has a clear yellow or yellow-brown color. So-called commercial stones have a color of at least 7.
| < или = 0,29 ct | > or = 0.30 ct | GIA | Description |
| 1 | 1
2 | D E | Bluish white |
| 2 | 3 | F | With a subtle tint |
| 3 | 4
5 | G H | Grayish white, yellowish white With a slight tint of yellow |
| 4 | 6
7 | I J | White with a subtle color tint |
| 5 | 8 (1-5) | K-L | Pale yellowish |
| 6 | 6 (1) | M-N | Yellowish tint |
| 7 | 9 (1-4) | O-R S-Z | Yellowish tint Yellow |
Diamonds, like most other stones of mineral origin, have natural inclusions and defects in their structure. The fewer there are, the more valuable the diamond. Absolutely transparent diamonds are practically never found in nature; we can only talk about the purity of a diamond under tenfold magnification. If no defects are found, the stone is recognized as a pure diamond. When determining the clarity of a diamond, the number and nature of defects are determined, as well as their size and location in the diamond. Diamond clarity is assessed at 10x magnification using a magnifying glass or a special microscope.
| Picture | < или = 0,29ct | > or = 0.30ct | GIA | Description |
| 1 | 1 | IF | Clean under a magnifying glass | |
| 2 | 2 | VVS1 | Very, very small inclusions | |
| 3 | 3 | |||
| 4 | VVS2 | |||
| 4 | 5 | VS1 | Very small inclusions | |
| 5 | 6 | VS2 | ||
| 7 | SI1 | Small noticeable inclusions | ||
| 7a | SI2 | |||
| 6 | 8 | SI3 | ||
| 9 | I1 | Inclusions visible to the naked eye | ||
| 7 | 10 | I2 | ||
| 8 | 11 | I3 | ||
| 9 | 12 |
“Diamonds are a girl’s best friend,” says the famous song. And every friend needs to be known, as they say, to the depths of his soul. Diamonds are no exception. How to understand the world of jewelry terms and choose the right stone? What should you pay attention to when making such a significant purchase? Let's try to figure it out.
Why are diamonds valued?
Everyone knows that a diamond is a cut diamond. And the fact that nature does not create so many of these stones is also a known fact. And even the fact that diamond is the hardest known mineral is not news either. So what is the most important characteristic of diamonds?
And what attracts jewelers to a diamond? There is only one answer - shine. The name of the stone itself is translated from French as “brilliant”. When light is reflected in a diamond, it shimmers with all the colors of the rainbow. Diamonds reflect artificial light best. It is under the light of lamps that the brightness and playfulness of the stone appears in all its glory. By the way, this is one of the reasons why wearing diamond jewelry until 5 pm is considered not quite decent.
Profitable investment
Now the fashion for wearing diamonds “everywhere and always” has passed. Buying a diamond ring is seen more as an investment than a determination of status in society. Compared to other gemstones, diamonds do not age over time. They are afraid of a direct blow from a hammer or stone. Other external factors are unimportant for them. And from an investment point of view, it is necessary to study how and how diamonds differ from each other. And what characteristics of diamonds are preferable in different cases.
Assessment according to the 4C system
There are not many diamond-producing countries in the world. And they are located in different parts of the world. But there are many more buyers. And everyone wants to buy, if not the most beautiful, then the most “correct” stone. The world practice of diamond evaluation has been established for a long time and is based on the fact that the characteristics of diamonds are described by four indicators: weight, color, clarity (transparency) and cut. Until a stone has been cut, it is just a diamond. No play of light or jewelry significance. Only a properly and professionally cut stone is capable of refracting light and sparkling. And be called a diamond. Actually, the 4C system got its name from the first letters of the words in English, which characterize the class of a stone: carat (weight), color (color), clarity (purity), cut (cut).
Diamond weight
Weight, as with all precious stones, is measured in carats. 1 carat is 0.2 grams. This is exactly how much 1 grain of carat wood weighed, which has been used since ancient times as a standard measure of weight for jewelry. The modern carat is divided into 100 parts. Because the weight (and size) allows a diamond to be classified into one of the groups: small (up to 0.29 carats), medium (from 0.3 to 0.99 carats) and large, or solitaire (more than 1 carat).
A diamond weighing more than 6 carats is destined to be sold only at a closed auction. Of course, other characteristics are also important here, but the weight alone is enough for the cost of such a giant to be sky-high. Therefore, those who want to purchase a large diamond prefer to do it behind the scenes.
Small stones are graded by diameter, not weight. But for large and medium-sized stones, it is a mistake to believe that the larger the diamond, the heavier the diamond. The characteristics of the stone sometimes make it possible to make a unique cut, which, with a large diameter, will give a relatively small weight.
Defectiveness of diamonds
Of course, you always want to buy the best. But in life we are guided by a rule: to choose the optimal price-quality ratio. And diamonds are no exception. There are very few absolutely pure stones in nature. And, accordingly, they are very expensive.
Most often in nature, diamonds are found interspersed with carbon and foreign crystals. It is very rare to come across samples with internal cracks. On the one hand, it is impossible to see all this with the naked eye. But on the other hand, when you purchase a diamond that does not sparkle in the light (or is very dull), and even more so when you invest in stones, you want the characteristics of the diamonds to be decent.
There are several standards by which the quality of diamonds is assessed. For example, the clarity of a diamond. The scale on which all stones are divided into categories depending on the quantity and quality of inclusions, according to the Russian standard, consists of 12 groups, where the 1st group is the purest diamonds, and the 12th is “dirty”. In fact, only starting from the 9th group can inclusions be seen without a microscope. Before this, a minimum of tenfold magnification under a microscope is required to detect defects in the stone.
This is probably why the American Diamond Clarity scale, which has 9 grades, does not treat the purest stones and stones with subtle inclusions differently. They belong to the same category.
Diamond clarity on different scales
Diamond color
Of course, the most popular are white diamonds. But just like absolutely pure stones, they are rare. Most often, we are offered diamonds of a yellowish hue in jewelry. But it is impossible to determine this by eye - human vision does not perceive such a subtle difference.
In nature, diamonds are found in different colors - from white to black. Until recently, the concept of “black diamond” was not used at all, and such stones were not used in jewelry. They were literally considered trash. But fancy yellow and blue diamonds are a completely different matter. If interestingly framed, they can become a real decoration of the collection.
In general, the concept of diamond color is very complex. The Russian standard uses terms such as “barely perceptible”, “blooming”, “barely noticeable”, etc. That is, assessing the color of a stone can be very subjective. Nevertheless, this characteristic of diamonds (a table that will help you understand the relationship between different standards should be in every store) plays an important role in determining the price. Up to the eighth color group, diamonds are considered white with various shades. Starting from the 8th, the color is defined as yellow. But here there are 3 subgroups.
Cut
Cutting a diamond is a very complex business. The quality of a cut can be described by three characteristics: symmetry, proportionality and polishing. It is according to these parameters, according to the American standard, that any diamond can be evaluated. In the Russian system, according to the quality of cut, a stone can be classified into one of the groups from A to G. Diamonds whose cut does not fit into the parameters specified for these groups are not subject to evaluation according to the specifications.
In addition to the quality of the cut, there is also the shape. This is something that can be assessed according to the simplest principle: whether you like it or not. Considered classic round form cutting of stones (sometimes called Russian). Oval, marquise, emerald, teardrop are all options for cutting diamonds.
How to choose a diamond
The price of a diamond is the sum of the ratio of all four quality indicators. Asking for a diamond marked 1/1 in a store (the first grade group in terms of color and clarity) means showing yourself not only as an ignoramus, but also as a pompous snob. Even demanding that diamonds have a 2/2 characteristic is also indecent. Diamonds most often go on sale with parameters of color 3-5 and clarity 3-6.
From an investment point of view, when choosing a diamond, it is better to compromise on color rather than clarity. Because various inclusions change the refractive ability of the stone, which means the diamond does not play in the light. Additionally, many imperfections can cause the diamond to crack if dropped. This will not only be offensive.
When choosing diamonds, pay attention to how the stone is hidden in the setting. The more the setting or its elements hide the facets of the diamond, the greater the likelihood that the product uses a low-quality stone.
Each diamond has a tag. It shows all the parameters: shape, number of facets, weight, color, clarity, cut group. It looks like this: 1 Kr57 – 0.43 – 4/3A. The first number indicates the number of diamonds in the product.
Diamonds of different clarity
As already noted, diamonds of different qualities are available for sale. The most common are 3/5, 4/5, 6/6. What are the characteristics of 3/5 diamonds, and how are they fundamentally different from 2/2, for example? First things first.
High class diamonds
In nature, these stones (with characteristic 2/2) are as few as absolutely pure ones. But according to standards, a few light dots are acceptable in diamonds of the 2nd clarity group. Several means no more than two. And it is impossible to see them from the side of the site with the naked eye. If a stone is labeled 2/2 in a store, you need to check its certificate, and you need a GIA (Gemological Institute of America) certificate.
The most popular diamonds are round, with a color and clarity of 4. The gemological characteristics of 4/4 diamonds make these stones a sound investment. The price for them never falls and gives a stable increase. In addition, these indicators of defectiveness and color are beyond doubt.
So, what is a clarity 4 diamond? Such a diamond may have 2 minor inclusions in the central part or 2-4 small defects in the remaining parts. Moreover, all this can only be seen with multiple magnification.
By the way, diamonds with defectiveness 5 may already be much cheaper than representatives of the 4th group. This is due to the fact that on small (up to 0.29 carats) stones, category 5 defects can already be seen without a microscope. But on large stones the inclusions are still not visible to the naked eye. Characteristics of 4/5 diamonds mean that there is a small “cloud”, crack or 5-6 tiny lines in the middle of the stone. If the inclusions are on other surfaces of the stone, then a small crack is allowed.
Large medium quality stone
If an average buyer needs the largest of diamonds, then it is necessary to pay attention to the 6th class of clarity. The larger the stone, the more inclusions are dispersed in it. Again, they can only be seen with multiple magnifications. But the cost of such diamonds is significantly less than their purer “brothers”. Characteristics of 6/6 diamonds: 8 light dots or a small inclusion of graphite are dispersed throughout the entire area; up to 5 dark dots are allowed.
There is an opinion that the size of the stone on the bride’s finger determines the degree to which the groom falls in love with her. Since defects in group 6 stones are indistinguishable in natural light, you need to choose a ring with just such a stone – large and beautiful.
The characteristics of diamonds (the table clearly illustrates this) significantly affects their value. The table shows the dollar price of medium and large diamonds.
Before purchasing a tiny but pure diamond, think about it: maybe you should lower the quality criteria, but increase the size.
How to choose a diamond. Carat, color, clarity, diamond cut
Source: VIBIRAEM.COM How to choose a diamond. Carat, color, clarity, diamond cut
When choosing a diamond, jewelers recommend the rule of four “Cs”, from the English carat (carat, i.e. weight), color (color), clarity (purity) and cut (cut).
The main indicator, of course, is weight. The more, the more expensive.
A good diamond should be colorless. If a perfectly colored stone is placed in water, it becomes invisible. This is where the concept of a “pure water” diamond arose.
The highest color class is first. Russian diamonds of medium size usually reach the first or second class.
The purity of a stone is determined by the absence of internal defects - cracks, inclusions. According to the accepted classification, first class is also the most expensive. In stones with low purity, defects can be seen through a regular magnifying glass. And according to this indicator, average diamonds correspond to class 3–4.
Cutting is a decorative element, but often determines the buyer’s choice. There is no competition here - the classic “round” shape. The number of edges must be indicated. It is an impossible task for a buyer to independently distinguish a fake diamond from a real one. If the stone is of normal size, the reputation of the store guarantees its authenticity. You can order an independent gemological examination.
Price issue. If the price tag says 1Kr57–0.24 1/5A, this means: one round stone, 57 facets, weighing 0.24 carats. Its color corresponds to class 1, and its purity corresponds to class 5A. Such a ring costs about 20 thousand rubles.
The leader in Russian sales is the people's diamond of 0.1 carats, its price with average quality characteristics is around 7 thousand rubles. A diamond of 0.5 carats will cost 140 thousand, and for 1 carat you will have to fork out 500–600 thousand rubles .
Russian diamond grading system.
The Russian diamond grading system is based on technical specifications (TU 117-4.2099-2002), in force since April 2002.
Cutting grade. A round cut with 57 facets (Kr-57) is accepted as the standard; there is also a round 17-sided cut (Kr-17), which is used for small stones. The specifications establish ranges of geometric cutting parameters according to which Kr-57 round diamonds can be divided into groups (in descending order of geometric parameters, symmetry, polishing quality) “A”, “B”, “C”, “D”, and Kr- 17 - into two groups - “A” and “B”. Diamonds of famous fancy cut shapes are divided into two groups - “A” and “B”. Fancy cut diamonds with an unconventional number and arrangement of facets belong to the “B” cut group.
The weight of a diamond is measured in carats to the second decimal place. To calculate the mass of a stone fixed in jewelry, use special calculation formulas.
There are three weight groups of diamonds: small (weighing up to 0.29 carats), medium (from 0.30 to 0.99 carats) and large - 1 carat and above.
Color assessment. Diamonds are classified into color groups from colorless with a gradual increase in the saturation of yellow, brown, and gray shades. The number of color groups depends on the weight. Small Kr-17 diamonds are classified into 4 color groups (1 - colorless stones). Small Kr-57 diamonds are classified into 7 color groups (1 - colorless stones). Medium and large diamonds are classified into 9 main color groups (1 - colorless stones) (see table), while several subgroups are distinguished in 6, 8 and 9: 6 and 6-1, from 8-1 to 8-5, from 9-1 to 9-4 (for example, 8-2 - lightly colored yellow, or 8-5 - yellow). Fancy colored diamonds belong to the first color group. I would like to note that there are practically no diamonds weighing 1 carat or more with characteristics of 1/1 on sale. Stones with these characteristics more expensive than diamonds with characteristics of 4/4 several times and may not be affordable even for very wealthy people. At the same time, in appearance, 1/1 and 4/4 diamonds are absolutely no different from each other.
Cleanliness assessment. Diamonds are classified into clarity groups depending on the presence of internal characteristics (inclusions, cracks, surface defects, the elimination of which will lead to significant weight loss), their quantity, location and color (characteristics visible through a 10x magnifying glass are taken into account). The number of purity groups depends on weight. Thus, small Kr-17 diamonds are classified into 6 purity groups, and small Kr-57 diamonds into 9 groups. For medium and large stones there are 12 purity groups (see table). The table shows that a diamond with a clarity of 5 on diamonds weighing up to 0.29 carats corresponds to a clarity of 7 for medium and large stones. Those. Defects and coloration that are difficult to see with the naked eye are detected only with characteristics of 7/7 (for medium and large stones). A trained eye, without the help of instruments, notices defects and color with characteristics of 6/6. Therefore, when purchasing large stones It would be more correct to pay attention to the color and size that catch your eye.
The final grade of the diamond is recorded in the following form: for example, Kr-57 0.35 3/4A. This means: a round cut diamond with 57 facets, weighing 0.35 carats, has a color group of 3, a clarity group of 4, and a cut group of A.
GIA system for grading diamonds.
Cut – cutting of a stone.
The quality of a diamond's cut is perhaps the most important component of all four in influencing a diamond's value, as a properly cut stone will look very beautiful and will have a lot of sparkle and play to it. When a diamond is cut correctly, light passes through the crown area, plays between the pavilion facets and returns back through the area, completely or almost completely reflected from the inner edges. If the cut is unsuccessful, then the light passing through the platform quickly reaches the edges of the pavilion and “leaks through” one of them, or leaves through the opposite lower edge of the diamond without having time to be reflected. The less light that refracts inside the stone and comes back out, the less sparkle your diamond will have.
Most specialists in precious stones They agree that the best diamond cut is based on a formula that gives the stone maximum brilliance. These formulas can be understood by studying the proportions of diamonds, but what is more important is how depth relates to the diameter of the diamond and how the diameter of the table relates to the diameter of the diamond.
Experts in the field of diamond cut classification have developed a table to help jewelers use it to give a diamond the ideal proportions. According to this table, diamond cuts (according to GIA) can be divided into the following categories: Ideal, Premium, Very Good, Good and Poor.
The ideal cut aims to give the diamond maximum brilliance and usually has a smaller platform, which has the added benefit of having a greater ability to diffuse light. This cut category only applies to round diamonds. Premium cut round diamonds are cut equivalent to a Perfect Cut with a wider table and slightly modified crown and pavilion angles. Very Fine cut diamonds reflect most of the light that passes through them, creating an adequate level of brilliance. Diamonds with this cut are obtained as a result of the fact that cutters deviate slightly from the intended proportions of the diamond in order to obtain a diamond that is quite large in weight. As a result, such diamonds have deviations in the size of the platform or the width of the girdle, although in other parameters they coincide with the parameters of diamonds in the “Ideal” or “Premium” category. A “Good” cut means that the stone reflects a lot of light passing through it. The proportions are deviated from ideal because the choice is made in favor of bigger size diamond when cutting, and not cutting off all the excess to get a small stone of the “Premium” category.
Clarity – purity of the stone.
When we talk about a diamond's clarity, we are talking about having distinctive characteristics on the outside and inside of the stone. While most of these characteristics are an integral part of a rough diamond, occurring in the earliest stages of crystal formation underground, some are a result of the intense pressure the diamond is subjected to during the cutting process. If you imagine the incredible pressure with which a diamond is born, it is not at all surprising that many diamonds have inclusion cracks, defects, air bubbles and particles of foreign mineral rocks, both on the surface and inside the stone. Clarity is assessed using a 10x magnification lens, taking into account the size, number, location and color of internal characteristics, as well as, in some cases, surface defects that cannot be removed by repolishing without significant loss of weight of the stone. All other things being equal, diamonds without intrinsic characteristics are considered more valuable. The GIA grading system distinguishes 11 clarity groups: from “Intrinsically Flawless,” a diamond that has absolutely no defects or inclusions even under 10x magnification, to “Imperfect,” a diamond that has serious flaws and inclusions visible even to the naked eye. glance.
F and IF (Flawless and Internally Flawless) – Pure and Internally Pure. These diamonds have no internal inclusions or are undetectable under 10x magnification. Very rare.
VVS1 and VVS2 (Very Very Small Inclusions) - Barely noticeable inclusions. Very difficult to detect at 10x magnification.
VS1 and VS2 (Very Small Inclusions) – Barely noticeable inclusions. The smallest inclusions are invisible to the naked eye and are difficult to detect at 10x magnification.
SI1 and SI2 (Small Inclusions) – Small inclusions. Tiny inclusions that can be detected at 10x magnification and in some cases (SI2) inclusions are visible to the naked eye.
I1 and I2 and I3 (Imperfect) – Noticeable Inclusions. Inclusions are visible both at 10x magnification and with the naked eye.
Color – color of the stone.
When jewelers talk about diamond color, they usually mean the presence or absence of color in a “white” diamond. The color directly depends on the chemical composition of the diamond and does not change over time.
Due to the fact that a diamond is colorless, like transparent glass, it transmits more light through itself than a colored stone, colorless diamonds sparkle more and play with light reflections. Due to the peculiarities of the diamond formation process, only a few specimens are truly colorless stones. The more colorless a “white” diamond is, the higher its value. These rules do not apply to fancy colored diamonds. Such diamonds have a bright fancy color - blue, pink, red, yellow, green. They are very rare and their cost is several times, or even orders of magnitude, higher than the cost of “white” diamonds.
When assessing the colorlessness of diamonds, many jewelers resort to the GIA professional color scale, which is divided into groups, starting with completely colorless diamonds and then increasing in saturation. yellow tint to the last group for yellow colored diamonds. Each group is designated by a letter Latin alphabet from D – colorless diamonds to Z – yellow diamonds. The same scale is used to evaluate the color of stones with a brown tint, taking into account the intensity of the brown color. Assessing the color of a diamond comes down to determining the color group. The coloring of yellow and brown stones with a color characteristic below Z is considered fancy. Diamonds with fancy colors have their own color groups; when describing such stones, the word fancy is used, then the color and its intensity are described. A set of standards is used to evaluate the color of diamonds.
Carat weight – weight of the stone in carats.
Carat is a unit of measurement used to determine the weight of diamonds. One carat is equivalent to 0.2 grams (200 milligrams). The word "carat" comes from the name of the seed of ceratonia, with which people in ancient times checked scales. Ceratonia seeds are so small and indistinguishable from each other that even the most modern technology is not able to measure the difference in the weight of two seeds exceeding a value of 0.003.
The process of diamond formation occurs only under special conditions, and usually natural ingredients, necessary for the formation of a crystal, can only be found in the mountains. Which means that large diamonds are found much less often than small ones. For this reason, the price of a diamond increases in direct proportion to its size.
The purity or transparency of a stone is the main criterion for determining its value, and a diamond is no exception. The cost of a diamond directly depends on the number of inclusions in the structure. Thus, a one-carat diamond with high quality indicators (for example, color/clarity = 1/1) costs around 30-35 thousand dollars, while a stone of the same weight with characteristics 8/12 is estimated at no more than one and a half thousand “green”. Diamond grading It is impossible to notice with the naked eye the difference in the clarity of a diamond with parameters 1/1 and the clarity of a diamond 3 3 or 3/4, therefore, you should not chase a perfectly clean stone. A diamond with average characteristics looks exactly the same as a clean one. but it costs an order of magnitude more. Defects in a diamond can only be seen with a 10x magnifying glass or microscope. Stones with clarity (8,9,10,11,12) are rated very low; these are cheap diamonds, but their purchase can hardly be considered profitable. It is better to compromise in color than in the transparency of the stone. Diamonds of the lowest purity groups have inclusions (flaws) visible to the naked eye, and can easily break if handled carelessly. If you are going to buy a defective stone, you should try to choose one whose inclusions are concentrated in the lower part of the pavilion. But it is better to refrain from purchasing diamonds with numerous defects in the area of the platform (upper part), since the stone will greatly lose in brilliance and optical properties. Manufacturers strive to mask the flaws of stones using all known methods - often defective diamonds undergo a refining procedure. Thus, cracks in the structure of the mineral are filled with a special substance with a high refractive index. In addition, jewelers usually “hide” the diamond’s defect area under the setting so that the diamond can be assessed without damage. jewelry didn't seem possible.Diamond 1 1
A “pure water” stone, also known as a 1/1 diamond, is the most expensive among other diamond color and clarity groups. This is not surprising, since the 1/1 characteristic is assigned only to the best diamonds.Nature of diamond purity defects 1
Diamond clarity is the number of natural inclusions in the stone's structure.
They can be either internal (impossible to get rid of by polishing without losing weight) or external (surface defects that can be removed by polishing). A GIA grade 1 or IF diamond may have only minor external imperfections that can be easily removed with secondary polishing. As for internal defects, they may be present in the structure of the diamond, but are invisible when viewed through a 10x magnifying glass, and it is with its help that the diamond belongs to one or another purity group.
The best diamonds
Diamonds 1/1 are quite rare guests as in jewelry stores, and in the bins of diamond dealers, and they cost several times more than stones of the same size, but with average characteristics. Usually such diamonds are ordered in advance.
Diamond 2 2
Diamonds with clarity 2 (GIA VVS1) are almost as rare in nature as the purest diamonds (quality group 1).
If the presence of internal defects is not allowed in stones with clarity 1, then diamonds with clarity 2/2 have inconspicuous light inclusions-dots.
Defectiveness of diamonds 2/2
It is almost impossible to see these tiny dots from the side of the site - if you look closely you can catch them by looking from the side of the pavilion. There should be no more than two dots, or the presence of a barely perceptible stripe is allowed. To purchase a diamond of clarity group 2 or VVS1, you sometimes have to wait several years. If you are lucky enough to find a 2/2 diamond, do not rush to buy - First make sure the information on the certificate is correct. To protect yourself from scammers passing off an “average” stone as a diamond of exceptional purity, only require a GIA certificate, the world's most authoritative gemological center. Diamond 3 3
Diamonds with a clarity of 3 (or VVS1) open the category of the best-selling diamonds, both set and unset.
The fact is that it is diamonds of 3 - 6 clarity groups that are excellent for investment,
they show stable growth and are an excellent way to save money.
Of course, you should only buy stones weighing one carat or more.
Defectiveness of diamonds of purity group 3
Internal defects of a 3/3 diamond at 10x magnification appear as three inconspicuous light dots (clouds, feathers) or two dark dots (stripes) Of course, if you take a microscope, you can find other “imperfections” of the mineral, however, when determining the clarity and color of a diamond, only 10x magnification is used and no more.For the buyer, these minor flaws are completely invisible, he does not see differences between,
for example, the first purity group and the third. The situation is similar with color assessment: experts, under certain lighting, compare the color of a diamond with standards, catch the slightest shades of color, blooms, and buyers examine stones with the naked eye and even with poor artificial lighting in the store. Naturally, there will be no difference between a 3/4 diamond and a 3/5 diamond. Diamond 4 4
One of the most popular diamonds are round diamonds with a clarity of 4 and a color of 3 or 4.
These diamonds (4/4) do not fall in price and give a good increase in value from year to year.
Of course, you shouldn’t expect super income, but they are perfect for preserving capital.
Diamonds with a clarity of 4 are generally not assigned controversial quality characteristics,
and for clear stones this is quite common (two different gemological centers may assign different characteristics to a stone).
Defectiveness of diamonds of purity group 4
It must be said that natural inclusions are a kind of “litmus test” that helps identify natural diamonds . The origin and authenticity of a diamond can be determined by the presence of natural defects.When determining cleanliness defects, their size is assessed,
number, nature, location, color of defects, etc. Looking at a diamond of 4th purity category through a magnifying glass, at least two minor inclusions can be seen in central area or 2-4 light dots (or 2 stripes) in other areas. For a 4/4 diamond, a small crack on the side is omitted. Diamond 5 5
A diamond with a clarity of 5 (VS1) belongs to the so-called medium clarity stones.
However, we need to make a small clarification: for a large diamond, transparency 5 is a very good characteristic,
but a small stone (up to 0.29 carats) with a purity of 5 is considered frankly defective.
This is due to the fact that in large diamonds the difference between clarity groups 3 and 5
(and the colors too) are impossible to notice with the naked eye,
but the difference in clarity for small diamonds is visually noticeable.
That is, visually a 4/5 diamond will be indistinguishable from a 5/3 diamond (with a weight of 1 carat),
and the difference in price will be significant.
Defectiveness of diamonds of purity group 5
The study of the location, size, and nature of inclusions is comparable to human fingerprint identification procedure. Synthetic diamonds do not have natural inclusions, their physical and chemical properties are now close to those of diamonds, therefore, only the defects of the stone prove its naturalness. Diamond clarity 5 is a small light cloud (or crack or 5-6 light lines) in the center of the stone. If the inclusions are in the peripheral part, then for a 5/5 diamond, three small cracks are allowed. Diamond 6
A clarity 6 (VS1) diamond is an excellent option for buyers who want the largest marketable diamond possible on a limited budget.
Diamonds of clarity group 6 are in great demand in European countries,
but for some reason Russian buyers are scared off by the number 6.
Meanwhile, a 6 6 diamond is an average quality diamond,
the most common quality group.
But stones weighing more than one carat in most cases look the same regardless of their clarity.
A 6th grade diamond is visually identical to purer stones.
The difference can only be seen with a 10x magnifying glass (this is about eight small light inclusions,
dispersed over the entire area of the stone,
or five dark dots or a small inclusion of graphite).
In natural light, these defects are completely invisible.
And since there is no visual difference, why overpay?
Diamond 7
Diamonds of purity group 7 (SI1) are characterized by multiple natural inclusions in the structure.
In this case, the characteristics of the diamonds will be the same, but the nature of the inclusions will be different.
Everyone chooses what they like. We can only advise one thing: if you are offered several diamonds of clarity 7,
Diamonds without playing
When buying a diamond, you need to take into account a lot of nuances, study dozens of offers and, with a limited financial budget, decide for yourself the question:
What do you have to sacrifice for the weight of the stone? Color or purity?
Clarity is a kind of test of a diamond, one of its main parameters.
When it comes to diamonds with a clarity of 10, 11, 12, it is better not to sacrifice anything, especially your money.
These are diamonds without “play” and shine.
They have numerous graphite and other inclusions, as well as cracks along the entire diameter of the stone.
Defects are noticeable even to the naked eye and negatively affect the refractive and reflective properties of the diamond.
Luxurious radiance and mesmerizing play of colors? Not with these diamonds. Another minus is numerous cracks.
If a diamond suddenly falls out of a ring, it is quite possible that it will break. There can be only one recommendation here - give in mass of stone,
give up the color of diamonds, but take a clarity of at least 8.
Industrial diamonds
Industrial or industrial diamonds are much more common than jewelry diamonds, and their cost is much lower than jewelry diamonds. Industrial diamonds are mined in more than thirty countries. These are stones with numerous defects that there is no point in cutting. However, even low-quality industrial diamonds still have the highest hardness in the world, and therefore are widely used for industrial purposes. They are used mainly as an abrasive substance. Industrial diamonds can be found in diamond drill bits, dies, cutters, electronic devices, etc.Characteristics of diamonds that you should pay attention to first
Typically, independent certification of stones in many cities around the world is carried out by special gemological certification centers and private gemologists. But no matter how much you trust the experts, when choosing diamonds, additional knowledge will not hurt you. Of course, without significant practice, it is unlikely that you will be able to see all the subtleties of the stone you are purchasing, but, nevertheless, you will not get lost in all these letters and numbers after familiarizing yourself with the basic information.
So, the value of a cut diamond is influenced by four main characteristics, which add up to: "4C" system. This diamond grading system includes the following concepts: “carat” (ct, k) - weight, “color” - color, “clarity” - clarity and “cut” - cut. The combination of these characteristics determines the price of the stone.
Estimating the value of a diamond.
There are quite a few subtleties in this process, but in general terms we can say that the cost of diamonds, with other similar characteristics, always increases exponentially with the weight of the stone. The lower the number (or the closer to the beginning of the alphabet the letter) characterizing the color and purity of the diamond, the more expensive it is. The quality, appearance and proportionality of the cut are also important in judging. Fancy diamonds are graded according to a special scale. Next are the nuances of the characteristics:
Carat (weight).
Measuring the weight of a diamond in grams is impractical. In nature (and on sale), cut diamonds weighing even around 1 gram (5 carats) are extremely rare and very expensive, and small and medium-sized stones (up to 0.2 grams, which exactly correspond to 1 k) are much larger. Therefore, since ancient times, a constant value for measuring the weight of a diamond has been adopted, based on the weight of 1 seed of the Carib tree “carat”, equivalent to 0.2 grams.
For convenience, all stones weighing up to 0.29 carats are considered small, over 0.3 and up to 0.99 carats - medium, and more than 1 carat - large. By the way, the term “solitaire” refers exclusively to large diamonds. And proper names (“Korloff Noir” - 88 ct, “Great Mogul” - 279 ct, “Orlov” - 190 ct, etc.) are given to cut diamonds weighing more than 25 carats. The weight of a diamond less than 1/100 (0.01) carat is not specified and is considered diamond chips.
Transitional masses of diamonds.
Although as the mass of the stone increases, its value increases, this process occurs unevenly (intermittently). A sharp jump in price occurs at certain values (0.3 ct, 0.5 ct, 1 ct 1.5 ct, 2 ct, etc.), which are called “transitional diamond weights”. Knowing this pattern will allow the buyer to save money by purchasing, say, a stone of 0.48 ct rather than 0.5 ct - the difference in weight (and visually) is negligible, but in price it is very significant.
Color
Often, the average person perceives the color of a diamond as “steel,” “white,” or “transparent.” For a specialist, all the nuances of colors and shades are important - because of this, the price of a stone can rise and fall with a huge difference. An important condition for determining the color of a diamond is a 10-fold magnification and comparison with a standard using the selection method, since the difference between “neighboring” colors can be very arbitrary. It is even more difficult to determine the color of the stone in the product - its removal is required for certification.
The color of a cut diamond can range from very rare, virtually colorless (“pure water”), through a scale of shades of grayish and yellowish, to brownish.
A separate type are “Fancy” diamonds, which have obvious rich shades - black, brown, green, pink, blue (the most unique ones are bright red and blue). They are extremely rare and are valued on a different scale; they are often incredibly expensive, outshining “white” diamonds. Here it is important to understand the difference between a unique fancy diamond and its cheap dark-colored “brother.”
IN different countries There are different color scales for diamonds, but they are easily comparable and have similar criteria.
Diamond color grading system in Russia.
In domestic jewelry practice, the weight of the stone matters, so three scales are used:
- for 17-facet cut diamonds, the number of colors is divided into 4 groups;
- for 57-facet diamonds from the “small” group (up to 0.29 ct), the number of colors varies from 1 to 7;
- For all other 57-facet diamonds (from 0.3 ct), a different scale is used, implying 9 color groups.
International Diamond Color Grading System .
The international system (GIA) differs from the domestic one in the absence of division of color scales according to the weight category of the stone.
All color values for "white" diamonds range from D to Z, where the price drops as the letter range increases to the right (and the color "darkens").
Fancy colors of diamonds are assessed according to a special scale of color standards, where, on the contrary, the darker, more saturated the shade, the more expensive the stone.
Clarity (purity/defectivity).
The quality and, accordingly, the price of a diamond is also affected by the presence (absence) of inclusions of natural origin inside the stone, such as bubbles, turbidity, cracks, inclusions, etc. This is a completely natural phenomenon for a mineral, but that is why a large number of diamonds have a very low cost. And only a small part of the mined material is turned into high-quality diamonds.
As with color determination, 10x magnification is used to determine whether a stone is defective. The degree of visibility of these inclusions through a magnifying glass, as well as with the naked eye, is a criterion for the purity of a diamond.
Domestic system for assessing the purity of diamonds.
Our system, just like with color, takes into account the weight and cut of the stone, only the ranges of groups increase slightly: diamonds with 17 and 33 facets - from 1 to 6, for diamonds with 57 facets - up to 0.29 carats from 1 to 9, for stones from 30 carats and above - from 1 to 12.
International system(GIA).
Unlike the alphabetic one (in alphabetical order) color designations, the international diamond clarity scale is indicated by an abbreviation with the addition of numbers (degrees) of defectiveness of the stones. For example, the ideal clarity of a diamond has the index “F” (Flowless – flawless, free of inclusions), and the worst option is indicated by the letter “I” (Imperfect – imperfect, with noticeable inclusions) with an index of 1, 2 or 3.
Cut (cut).
Processing the mined mineral is of course of paramount importance. In most cases, it depends on the professionalism of the jewelry maker whether a dull, shapeless stone will sparkle with amazing brilliance or become mediocre “glass.”
Rough diamonds can be cut in a number of ways, of which the round “brilliant” cut is the most popular, preferred in more than 90% of cases, despite its high cost. This type of cut allows from 57 (“classic”) to 17 (simplified version) facets. “Diamond” processing is the most optimal for revealing the unique optical properties of the stone.
All other types of cuts belong to the fancy group, which, in turn, are wedge (round-oval proportions) and stepped (angular, polygonal).
The most popular types of fancy cuts are: oval, marquise (oval with pointed top and bottom), pear (drop-shaped), princess (square), heart, baguette (rectangle), "emerald" (polygon).
Diamond cut quality groups.
The maximum brilliance and play of a diamond are achieved as a result of precise adherence to proportions, calculated according to a certain formula, which takes into account the following ratios: depth - diameter of the stone, diameter of the platform - diameter of the stone.
According to the GIA international system, the quality of diamond cutting can be: “Ideal” (ideal), “Premium” (excellent), “Very Good” (very good), “Good” (good), “Poor” (good quality). The foreign cutting quality system (geometric conformity, polishing quality, symmetry) is very convenient from a visual point of view, in contrast to the domestic one, denoted by letters:
- for Kr-57 – ranges from “A” to “G”;
- For Kr-17 and fantasy forms - “A” and “B”;
- non-traditional cut proportions are usually classified as group “B”.
By the way, often the proportions of a diamond cut are violated not because of the unprofessionalism of the master, but because of the need to preserve the size of the stone as much as possible.
What does the tag say?
After reviewing the characteristics that make up the price of a diamond, we can understand what is being said on the tag attached to the product. The characteristics of the stone are placed opposite the “insert” column. Typically the information is provided in the following form:
Br. Kr. 57 1 pc. 3/4 A 0.07 ct
“Br. Kr." - type of cut, here - “round diamond”;
“57” - number of faces;
"1 PC." - the number of stones with the same characteristics in the product;
“3/4” - color/purity;
“A” - cut quality;
“0.07 ct” - weight in carats.
In addition, the condition of the tag itself is important, because it is the “face” of the manufacturer, and reputable companies do not skimp on it. Usually the tag is located on a heavy-duty thread attached to the product, where there should be a seal-imprint with the manufacturer's emblem. It must contain information about the manufacturer and its legal address, name of the product, metal and sample, insert (characteristics of all stones), article number, regulatory documents, price for the entire product, size, and have a quality control department stamp.
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