Myths and legends

What are the purest diamonds called?

Indeed, a diamond as a gift is evidence of high feelings. But diamond jewelry is a very valuable acquisition not only for its beauty, but also for its cost. The price of such products is made up of certain qualities of diamonds, which together affect the amount of the bill to be paid. When presenting a ring with diamonds as a gift, it is not at all necessary to demonstrate its price, but other characteristics may not be superfluous for its owner, although it is quite difficult for an untrained person to understand them. What does this code mean, for example: Kr-58 0,46 3/4. The Four Cs Principle The cost of diamonds is determined by the principle of the “four Cs”: weight, color, clarity and cut (in English it looks like carat weight, color, clarity, cut). These four characteristics are hidden in the mysterious code that accompanies diamond jewelry. C arat weight determines the mass of a diamond, measured in carats. This system of measures has come down to the present day from ancient times, when carob seeds – carats – were used as a measure of mass. It was they who were used in the era of the Roman Empire as a measure of mass – each grain weighed the same (about 0 grams). Nowadays, precious stones are measured in carats. Naturally, the more a diamond weighs, the larger its size. Diamonds weighing up to 0,29 carats are considered small (in the international classification system they are called melee); medium (melange) – from 0,3 to 0 carats; Diamonds weighing more than 99 carat are classified as large. Large diamonds are rarely used in jewelry together with other stones – their beauty does not need any additions. Single large diamonds are called solitaires. As a rule, diamonds weighing no more than 1 carats are sold in jewelry stores. Larger ones are sold at auctions. Cut (cut) is what turns a natural mineral (diamond) into a piece of jewelry. This criterion is the most difficult to evaluate, since it is based, first of all, on aesthetics – the shape, brilliance, and surface structure of the diamond. However, relatively recently (no more than a hundred years ago), evaluation criteria were defined based on optical laws, or more precisely, on the high dispersion (light reflection) of diamond. Light inside a cut stone is decomposed into spectral components. At the same time, the lower edges, like mirrors, reflect and multiply the penetrating rays. When cutting a diamond, it is important to strictly observe the proportions, otherwise the proper effect of light play will not be achieved. The necessary parameters were first obtained by mathematician Marcel Tolkowsky. Diamonds with Tolkowsky parameters have long been considered ideal, and they are the standard to this day. Diamond cutting, which was carried out by master jewelers at the Soviet enterprise “Crystal” in Smolensk, was recognized as one of the best in its time. Cutters here achieved such high quality diamonds that the term “Russian cut” became common throughout the world as a characteristic denoting a very high level of processing. The cut of a diamond also determines its shape. A classic diamond is round in shape and has 57 facets. It is these proportions that allow the diamond to reflect almost all the light falling on it. But, naturally, jewelers, trying to create original jewelry, give diamonds not only a round shape. Diamonds of non-classical (i.e. not round) shape are divided into two types – wedge and step, and are called fancy. Such cuts as pear, marquise, heart, baguette, princess are known – in total there are 17 types of fancy diamond cuts. Round cut diamonds are divided into four groups depending on compliance with technical parameters: A – ideal parameters; B – quality parameters; B – satisfactory; D – quality below satisfactory. Fancy cuts come in only categories A and B. An ideal diamond should be absolutely transparent, because it is no coincidence that diamonds are called “tears of the earth.” But, as you know, nothing ideal exists in nature. Diamonds, like other natural minerals, have certain inclusions in their structure. The fewer there are, the higher the cost of the diamond. Clarity (transparency) is determined according to specially developed standards. In Russia, the clarity of diamonds is assessed on a ten-point scale, which indicates acceptable inclusions that are visible under tenfold magnification. A diamond with a clarity of 1 does not contain any inclusions – it is called a pure diamond. In international practice, the most common standard for grading diamonds is the GIA standard, developed by the Gemological Institute of America. According to the GIA standard, absolutely pure diamonds are designated by the letters FL (flawless). Diamonds rated at 2 and 3 points according to Russian standards (on the GIA scale they correspond to categories IF, VVS 1 and VVS2) are considered to be of a high degree of purity and, accordingly, more valuable. Color (color) is a special criterion. As a rule, diamonds are colorless. But they can also have a certain, subtle shade. Diamonds with a barely noticeable bluish tint are valued on par with colorless ones. Those that have a slightly yellowish tint are rated lower. At the same time, bright yellow diamonds (jewelers call them “canaries”) are more expensive than classic colorless ones. Of the colored diamonds, brown diamonds are the most common (they are also called “cognac” or “cinnamon”). Rarity – blue, pink, purple and azure diamonds. Red and green diamonds are a real sensation. The cost of such diamonds can be hundreds of times higher than the cost of a regular colorless diamond of the same size. Modern technologies make it possible to artificially color transparent natural diamonds, producing diamonds of different shades. In this case, the diamond does not lose its properties; it still remains a precious stone. But, of course, a colored diamond born from nature is a completely different phenomenon. To determine the color characteristics of diamonds, there are also Russian and international standards, according to which all possible colors and shades are divided into groups. In the Russian classification, groups are designated by numbers, in international ones – by a letter code. The black diamond is a completely new phenomenon, since black diamonds have never been considered as jewelry or even “near-jewelry.” It was believed that this was a purely technical mineral that could not become decoration. Black diamonds acquire their color due to the content of iron oxides in their structure. The trendsetter for black diamonds was Fawaza Gruosi, the founder and chief jeweler of the de Grisogono company, the success of which turned out to be so resounding precisely because Gruosi offered the world the “carbonado” – a black diamond that adorned not only traditional rings, earrings and brooches, but and men’s cufflinks, watches and even mobile phones. Fawaza Gruosi made another “revolution” in jewelry, showing that opaque diamonds can also become a valuable raw material for the production of diamonds of special quality. I cy diamonds (matte diamonds) were first presented at the Basel exhibition in 2002 and have not gone out of fashion since then. For matte and black diamonds, the standard clarity and color ratings do not apply. But it is simply impossible to be mistaken that this is exactly the diamond in front of you. Unset diamonds purchased separately, without jewelry, are accompanied by a mandatory certificate issued by gemological centers and laboratories accredited by the Assay Board. Retail trade in diamonds without certificates is prohibited in Russia. When purchasing loose diamonds abroad, you also need to worry about the presence of a certificate (the most common are GIA certificates): firstly, this document will be required at customs; secondly, without a certificate, problems may arise if you later decide to sell the diamond. In addition, the certificate makes it possible to find out the source of origin of the stone (the country in which it was produced). Set diamonds are sold without certificates. All the necessary characteristics are stated on the jewelry label in the description or in the form of an alphanumeric code, which looks, for example, like this: Kr-58 0,46 3/4, where: Kr-58 – cut type (round, 58 faces); 0,46 – caratura (diamond weight). For small stones, the grouping caratature is indicated (37/0,46 would mean 37 stones with a total weight of 0,46 ct). For diamonds of the “melange” and “solita i re” categories, the caratature is given for each stone. If a piece of jewelry combines a group of small diamonds with a larger stone, the characteristics will indicate two caratatures – for the group of stones and for the larger diamond. And finally, the last digits in the form of a fraction indicate the color and clarity of the diamond. Diamonds of “pure water” (i.e., absolutely transparent), belonging to group 1 on the color scale, are practically never found in retail sales – they are very expensive and rare jewelry, just like stones of group 2 of color and transparency. Therefore, you should not look for jewelry with characteristics 1/1 and 2/2 in stores. As a rule, diamonds with characteristics of 3/3, 4/4 (the most common option) and 5/5 are sold in jewelry stores. 4/4 diamonds have a slightly yellowish tint and a small number of dark and light spots that are not noticeable to the naked eye. They can only be viewed at tenfold magnification. In 3/3 diamonds, yellowness and inclusions are even less present. But stones with characteristics of 5/5 are no longer considered to be of sufficient quality. Natural defects affecting color and transparency, are barely noticeable only in small stones with such characteristics. Connoisseurs of jewelry with category 5/5 diamonds tend to neglect it. However, if the budget is limited, such jewelry quite satisfies not too demanding buyers. Buying earrings with diamonds of such characteristics, but with stones of sufficiently large carat, is still a very good gift. Diamonds are typically graded using the 4C system introduced by the Gemological Institute of America (GIA). The 4C system includes four assessment criteria: Clarity and color are the main characteristics of diamonds that play a role in determining the value of a stone.

International grading system

Cleanliness

A diamond’s clarity is the degree to which inclusions and surface blemishes are present. Because diamonds are formed deep in the ground, extreme temperatures and pressures create unique markings on them. Unmarked diamonds are rare, and rarity affects the value – such stones are more expensive. The quality of diamonds in terms of clarity in the international grading system is usually designated by letters from FL to I 3. Gemstones with the characteristic FL are flawless diamonds, I 3 are those with obvious inclusions such as air bubbles, crystal inclusions, etc. Every diamond is unique. None of them are absolutely perfect at 10x magnification, although some examples come close. These diamonds are called flawless. They are so rare that most jewelers have never seen them. Like the GIA color scale, the clarity grading system was required because jewelers had previously used terms that were easily misinterpreted. Today, even if you buy a gemstone from another country, the jeweler will likely use terms like VVS 1 or SI 2, although he may speak French or Japanese rather than English. Purity assessment is made at 10x magnification or with the naked eye, taking into account the size, quantity, location and color of internal characteristics, as well as, in some cases, surface characteristics. When assessing the clarity of diamonds, surface imperfections (pits, scratches) are also taken into account, which cannot be removed by repolishing without a significant loss in the weight of the stone. All other things being equal, diamonds without intrinsic characteristics are considered the most valuable.

Classification of diamonds by color and clarity

The international expert assessment system distinguishes 11 diamond clarity groups, they are presented in the table below. However, most stones fall into the VS or SI categories. Flawless, no inclusions or stains visible at 10x magnification IF (Internally Flawless) No inclusions, surface blemishes visible to a qualified appraiser under 10x magnification VVS 1 and VVS 2 (Very, Very Slightly Included) Tiny inclusions that range from subtle to very subtle are visible to an experienced appraiser at 10x magnification VS 1 and VS 2 (Very Slightly Included) Very minor inclusions that range from difficult to see to fairly easy to see SI 1 and SI 2 (Slightly Included) Conspicuous inclusions ranging from simple to very easily visible at 10x magnification I 1, I 2 and I 3 (Included) Inclusions are obvious at 10x magnification and may affect clarity and brightness

Color

The color of a diamond is something that is invisible to the eye. Diamonds are valued by how close to colorless they are: the less color, the higher their value. The exception is fancy diamonds (pink, blue, etc.), which fall outside this color range. Most diamonds in the jewelry chain are colorless to nearly colorless with minor shades of yellow or brown. Because the light source and background significantly influence color perception, diamond color is assessed under standardized conditions. GIA color graders submit their independent opinions to the system. At this stage, evaluators have no information about the color decisions entered into the system earlier. As a result, the color scheme is determined if there is a sufficient number of consistent opinions.

Color rating scale

The GIA Diamond Color Grading Scale is the industry standard. The scale consists of Latin letters from D to Z, where D is colorless and Z is light yellow or brown, that is, the gradation occurs as the presence of color increases. Each letter grade has a clearly defined range of color characteristics: a group of colorless stones, almost colorless, with a faint color, very light, light. Grading diamonds by color is done by comparing them to stones of a known color under controlled lighting and clear viewing conditions. The difference between some colors is so subtle that it is inaccessible to the naked eye. But these small differences have a significant impact on the quality and price of diamonds. Many people wonder why the scale does not start with the letter A. Before GIA developed the D-Z color gradation scale, a number of other systems were poorly used. These included a system with a letter designation (A, B and C, with a few A’s for the best stones), a number system – Arabic numerals (from 0 to 3) and Roman numerals (I, II, III), as well as descriptive characteristics of diamonds , such as “blue gem” or “blue-white”. The use of such rating systems has led to inconsistency and imprecision. Because the creators of the GIA color system wanted to start over, they chose the initial letter D as a letter grade not typically associated with superior quality.

Russian diamond grading system: clarity and color

In Russia, the main document used in evaluating diamonds and developing a price list for them is TU 117-4.2099-2002 dated April 1, 2002. The classification of diamonds by clarity and color groups is given in the tables in accordance with technical requirements. The Russian system provides 12 purity groups.

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