The price of diamonds: how to establish their value
In the imagination of consumers, i diamonds they are probably the most valuable precious stones, protagonists of jewels with a strong symbolic meaning, such as the solitary rings. But how do you establish the price of diamonds? The factors that contribute to determining the cost of a diamond are numerous and concern the different characteristics of the stones.
We must first consider that natural diamonds are one of the rarest minerals in the world. On average, to obtain 1 carat, or 0,2 grams of diamonds, it is necessary to extract 3-4 tons of rock from a diamond deposit, which becomes 15 tons if, instead of rock, sand and gravel are worked, as in alluvial deposits . Subsequently, the rough stone extracted from the mine must undergo several treatments before being cut into the shape of a gem.
The Rapaport Price List, the official diamond price list
There is a tool that constitutes the official reference to determine the price of diamonds cut yourself. It's about the Rapport Price List, the price list released every week by the Rapaport Group. It was designed by Martin Rapaport, a Belgian entrepreneur who in the 70s had started working in Antwerp in diamond cutting and who in 1976 moved to New York. In 1978 he began to publish his own weekly report, indicating the price of diamonds, which quickly became the benchmark for the sector.
Martin Rapaport also promotes social responsibility in the diamond industry: he is indeed a supporter of Kimberley Process, the international agreement which since 2002 has certified i conflict-free diamonds, ensuring that profits from extraction are not used to finance wars, acts of terrorism or criminal organisations. The Rapaport Group guarantees respect for the rights of workers engaged in diamond mines, particularly in Africa, and the ethical trade in diamonds.
How the PRICE of diamonds is established
The Rapaport Price List is published every Thursday at midnight and contains guidelines for establishing the value of diamonds expressed in dollars. It is not a price list for retailers and does not indicate the retail cost of diamonds, but it does offer indications for having an estimate of the value of the stones. The final price of a diamond, therefore, can be higher or lower than that indicated by the report, because it depends on various factors in addition to those reported, such as the proportions and symmetry of the cut and how this is performed. There are also other more specific characteristics which cannot all be listed in the price list, as this would become very complicated to interpret.
The price of diamonds is extremely precise and can be parameterised: the same stone valued by two different experts, for example in New York and Antwerp, would receive a quotation with the same value.
The main characteristics of the price of diamonds
- The dimension
The larger the diamond, the rarer it is and the higher its value. Prices for round diamonds range from 1 cent of a carat to 10 carats, while other shapes are priced from 25 cents of a carat to 5 carats.
- The color
The criteria for evaluating the color and clarity of diamonds are based on the parameters of the Gemological Institute of America (GIA), the American research institute which represents the highest authority in the sector. The more the diamond is colorless, i.e. tending towards white, the more its brightness is exceptional. In fact, in ancient times, the classification of color was done by attributing to diamonds the wording "exceptional white extra plus", corresponding to the current letter "D", i.e. the most beautiful and brightest diamond in existence.
- Purity
Diamond clarity represents the transparency of a gem. The evaluation examines any internal (inclusions) and external (defects) imperfections. A diamond is considered pure if it has no visible imperfections under 10x magnification.
- Cutting
The cut greatly affects the price of diamonds and the price list refers to accurately cut stones. Medium cut or lower value diamonds can be sold and bought at substantial discounts as well.
The safety of certified diamonds
A quality diamond has a high price which corresponds to a high value. It is therefore important that this value is certified through an official document that describes the characteristics and quality of the stone. Certification is essential for attributing an objective value to the diamond, for example for insurance or even if you want to resell it. To make sure that the price of diamonds purchased is correct and that the stones are certified, the best choice is always to rely on professionals experts.