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How to determine the quality of gemstones?

During the cost assessment, everything is taken into account, up to a slight change in any of the specified parameters. So, natural, artificial stones, imitations have different prices.

It is not always possible to evaluate a product and the true value of the precious stone in it with the naked eye. In this regard, the services of gemological centers and laboratories involved in conducting examinations are becoming increasingly in demand abroad and in Russia. Based on the results, the client receives a gemological conclusion, certificate or report. Such documents usually do not indicate the cost, but they provide diagnostic results and analyze the characteristics. Based on this, valuations are often carried out.

In what cases is valuation of precious stones recommended?

Gemological examination and valuation are preferable in several cases. It happens that there is little information on the jewelry label or there are suspicions that the information provided is unreliable. At the same time, buyers often want to purchase more than just decoration. It is important for many to be sure that the cost of the product is adequate and will not only not fall over time, but will also increase. After all, as you know, over the past 50 years, prices for natural stones have been rapidly increasing, so they can be considered as investment objects.

Let us remind you that the cost of two outwardly similar stones can vary significantly: up to four orders of magnitude. So, a bright red stone weighing 5 carats will turn out to be a Burmese ruby ​​(price 200 dollars per carat) or a composite of ruby ​​and glass (price 000 dollars per carat). Not every buyer and seller will be able to see the differences. In this regard, documents issued by gemological laboratories increase the liquidity of unmounted jewelry and jewelry.

The main thing is to clearly understand that there are cases when the amount of possible damage (overpayment for non-existent quality) is much higher than the cost of the services of an expert gemologist. For example, when it comes to purchasing products with precious and semi-precious inserts, it is important to order an examination at a price of more than 40-50 thousand rubles. If we are considering a diamond item, revaluing it by color or clarity group by approximately 12 percent changes the final amount.

Determining the weight of a frame “by eye” is quite difficult. The calculation error sometimes reaches 10 percent. Without an expert opinion, it will not be possible to say whether a diamond weighs 1,01 carats or 0,96. The difference in price will be 50% or more!

It will not be possible to confirm color and purity without removing it from the frame. Note that the cost of a synthetic colored stone is several times lower than the price of the same natural one. The presence or absence of traces of refining also plays an important role in the evaluation of precious stones.

Experts from gemological centers constantly study jewelry and their properties, and therefore are able to carry out diagnostics and evaluation. And they turn to the services of specialists more and more often, because the assortment on the jewelry market is constantly changing. Synthesis methods are being improved, and today artificial stones are close to natural ones in appearance and some qualities. In most cases, only highly sensitive gemological equipment can diagnose treated stones.

How does cut affect the value of a diamond?

When evaluating a cut, attention is paid to the diamond’s proportions and finishing. These factors have a direct impact on the diamond and the “game”. High quality cut diamonds look better, more “alive”. Often diamonds are stored with distorted proportions, which also affects the diamond and the “game”. Today, special attention is paid to diamonds with an “ideal” cut, but there are several types of such stones, with slightly different proportions.

For example, diamonds with a smaller platform size give more “play”, while diamonds with a larger platform size give more diamonds.

Diamonds with a high quality cut cost much more than stones with a low quality cut. For clarity, we can give approximate discounts for round diamonds depending on the distortion of cutting parameters:

  • distortion of the shape of the site – 2-15% discount,
  • very thick girdle – 5-10%,
  • very thin girdle – 5-25%,
  • violation of the symmetry of the crown faces – 5-15%,
  • culet displacement – ​​2-5%,
  • reduced diamond height – 15-50%,
  • increased height – 10-30%,
  • low crown – 5-20%,
  • high crown – 5-15%.

Although there is no consensus on the proportions of an “ideal” diamond, it is an undeniable fact that a good cut allows a diamond to reveal its full beauty.

So, certification and assessment are completely voluntary decisions. The buyer can choose whether he needs information about the main pricing parameters of jewelry. We remind you that you are not risking anything except. your money.

You can find out more interesting information at the Gemological Center of Moscow State University.

“4C” system (principle“4C”: Carat (Weight), Color (Color), Clarity (Clarity), Cut (Cut), of which they are part color и purity, is the basis for determining the value of a diamond.

The 4C system has been widely used throughout the world since the second half of the twentieth century. Thanks to it, it is possible to justify the price during the dialogue between the seller and the buyer, in addition, buyers received a tool for orientation in various offers of diamonds, which as a result allows them to make a choice that will not be “excruciatingly painful” in the future.

The most correct (correct) sale will be one in which the buyer, with the help of an experienced expert (seller) or independently, has chosen a range of characteristics that suit him, including color and clarity groups, and has chosen the best (in his opinion) diamond from all positions that were offered to him

In fact, if the buyer has determined the boundaries of the budget for his purchase, then different diamonds may fall within this framework, and the choice must, as a rule, be made on one. Each of the components of the 4C system directly affects the cost of a diamond. The weight of a diamond is determined by an objective method on a scale, but there is a subjective factor in assessing color and clarity.

Although quite a few different instruments have been invented around the world and specific methods have been developed for a fair and unbiased assessment of the color and clarity of a diamond, the most authoritative laboratories in the world believe that the final word in assessing these characteristics remains with experts with experience and qualifications.

The cost of a diamond (precious stone) depends on how its color and clarity are determined, and this depends on the opinion of experts, which is subjective.

In the Color and Clarity Tables, the groups are formed so that a gemstone specialist (gemologist) can determine the difference between neighboring groups even with average qualifications. However, this difference is better visible in stones that are not attached to the product (unmounted) from the crown side, subject to the necessary lighting and observation conditions, when compared with standards (samples) in color, and jewelry buyers, as a rule, view stones in conditions different from the necessary ones .

The situation is similar with the assessment of diamond purity: gemologists examine stones using tenfold magnification, and buyers see stones with the ordinary (naked) eye and, as a rule, the lighting is such that inclusions of a diamond (gem) can be hidden against the background of the play of the stone and light reflections.

Thanks to this, diamonds (precious stones) with characteristics that differ from each other, but are similar, will not differ from each other for the undoubted majority of buyers.

Thus, when selling, there may be a temptation to change the characteristics, and many sellers believe that no one will be able to distinguish 3/3 from 4/4 in a piece of jewelry. When selling jewelry, there are often precedents for changing one characteristic of a diamond (precious stone) to another.

A number of store representatives are of the opinion that it is generally impossible to determine the color and clarity group of a diamond (precious stone) in a piece of jewelry (in a setting). Therefore, there are stores where all diamond jewelry is presented in display cases with only 3/3 characteristics [“decent, good, awesome diamonds”].

Remembering that each diamond (precious stone) can pass through several hands, it is easy to imagine how at least one of its characteristics can change on this way to the consumer.

How to get between the streams.

And yet, how to choose the best characteristics of a diamond (precious stone) when purchasing? The highest diamond color and clarity grades are not always necessarily the most profitable/tempting for buyers.

In the international diamond market, the predominant demand is for the G, H, I color groups and VS and SI clarity groups. This fact reflects not so much the insufficient number of stones with higher characteristics, but the practicality of buyers who do not want to pay more for the unobvious. That is, the purchase of a diamond with a characteristic of color group D (1 according to the Russian classification) and a characteristic of quality group IF (1 according to the Russian classification) is a shock for the buyer’s wallet, but the delight of visual perception can also be experienced from a diamond of color G (4 according to the Russian classification) and purity group VS (4 according to Russian classification). Only a specialist can evaluate the difference in characteristics.

Sophisticated buyers and correctly impartial gemological experts give the following advice to buyers: reduce the color and clarity group indicator until the color (color shade) and inclusions (clarity of the stone) remain indistinguishable to the buyer’s eye without additional tools (magnifying glass, microscope) when normal conditions (lighting) in which the diamond (gem) will be worn.

When a buyer reduces the color and clarity characteristics to a certain limit, it gives him the opportunity to increase his diamond (gem) selection, and the savings on color and clarity can be used to select a larger size and better stone. cut.

Below are tables of correspondence between the characteristics of diamonds in terms of color and clarity according to the Russian specifications and the international grading system (according to GIA).

Jewelry tags in stores must display the characteristics of diamonds (precious stones) according to the Russian classification, which are more accurate than the international characteristics of the highest groups of color and clarity.

Diamonds with characteristics of 1/1 are practically not found on sale, and characteristics of about 6/7 are warily encountered by the majority of consumers. Because of this, as a rule, stores do not have goods for which there is a steady demand, and those that are available are in little demand due to their actual characteristics.

The jewelry trade in Russia insists that the characteristics of diamonds (precious stones) be indicated in accordance with current technical specifications (TU) for diamonds (precious stones) , which according to the law of the Russian Federation “On Technical Regulation” are not mandatory. The sales rules do not determine what characteristics of diamonds (precious stones) should be indicated on the jewelry tag: Russian or international.

It would be possible to defuse psychological wariness by switching to an international system, but this action would become unfairly inconvenient for those buyers, experts and sellers to whom the Russian assessment system has become familiar and understandable.

When selling jewelry using the Russian classification, it is necessary to explain to the buyer the specific characteristics of diamonds according to the Russian specifications.

For example, it should be noted that color and clarity groups are defined differently for small stones (weighing up to 0,29 carats) and for all others. In particular, the fourth color group for a small stone can become the sixth when this stone weighs from 0,30 carats (see conversion tables). Therefore, without determining the weight of the stone, the discussion about whether a diamond with characteristics 5/6 can be classified as bad or good is completely useless. For a large diamond these are very worthy characteristics, but for a small diamond they are modest and unimportant.

Responsibility for characteristics

To determine the color and clarity grade of most diamonds currently on sale, you need to have an understanding of “how to look” and at least have a magnifying glass.

When an inexperienced consumer reads a text description of color and purity groups for the first time, he may become confused in the intricacy of wording rather than clarify the issue.

Differences in diamond prices are based on subtleties that are indistinguishable to the consumer.

Therefore, if a buyer does not fully trust the diamond seller, he will choose another product and another seller in whom he has more confidence.

Abroad in the Russian Federation, conclusions (reports) of gemological laboratories are widely distributed, which provide information on the color and purity of diamonds, unbiased and professionally determined.

Sellers of jewelry stores in the Russian Federation rarely have an independent certificate or expert opinion.

When selling loose (unmounted) diamonds in a store, they must be available, but their volume is insignificant compared to the number of set (unmounted) diamonds.

Sellers in stores say that certificates (conclusions) are used in the West, but in our country certificates are not required, since each piece of jewelry must have a tag, which is quite enough.

The tag should include information about weight, color and purity. But, as a rule, the question of who established the characteristics of the stone that are written on the tag plunges store employees into confusion. While assuring that the fairness and correctness of the characteristics are beyond doubt, they cannot say which of the store employees is responsible for specifying them.

You can watch a video explaining this article here

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