Diamond selection secrets: From ore to gems

Recently, as the jewelry market continues to heat up, diamond as one of the "star products", its material selection process has attracted much attention. Diamond selection is not only a technology, but also an art, related to the final presentation of each diamond's brilliant light.

Diamonds, also known as diamonds, are crystals of carbon atoms formed under extreme conditions of high temperature and pressure. Natural diamonds are formed in the Earth's mantle layer 150-200 kilometers deep, after 900-1300℃ high temperature and 45,000-60,000 atmospheric pressure, after a long process of more than a billion years to crystallize. The cultivation of diamonds is through scientific and technological means to simulate the natural environment in the laboratory "growth" out, mainly HPHT method (high pressure and high temperature method) and CVD method (chemical vapor deposition method), the whole process only takes 3-4 weeks at the fastest.

From the mining site to the processing plant, the diamond begins its journey of material selection. At present, the world's main natural diamond producing areas are Australia, Russia, South Africa and so on. In the mining process, for every 1 carat diamond excavated, it is often necessary to blast 250 tons of rock, which shows how difficult it is to mine. Mined rough diamonds are like uncut jade, and it is the job of the selectors to select the rough stones with the most potential.

In the material selection process, there are several key criteria:

Carat weight: Carat is the unit of weight of a diamond, with 1 carat equal to 0.2 grams. In general, under the same quality, the greater the carat weight of the diamond, the rarer, the higher the value. For example, a 1 carat diamond may cost several times more than a 50 cent (0.5 carat) diamond.

Reng: Diamonds range in color from colorless to light yellow, and colorless diamonds are the rarest. In the international standard, D color represents completely colorless, is the top color, followed by E, F, G, etc., the color gradually deepened.

Clarity: Clarity refers to how pure the inside of a diamond is. Natural diamonds may have some mineral inclusions during the formation process, such as garnet, mica, etc., and the size, number and location of these inclusions will affect the clarity of the diamond. From high to low, the clarity is divided into FL (flawless), IF (internal flawless), VVS1, VVS2 (very weak), VS1, VS2 (weak) and other levels.

Cutting: Cutting is the key factor affecting the diamond fire color. A good cut allows the diamond to reflect and refract light to the maximum extent possible, giving off a brilliant glow. Internationally commonly used cutting grades are 3EX (perfect cutting), VG (very good cutting), G (good cutting) and so on.

It is worth mentioning that Chinese scholars have made major breakthroughs in the field of diamond research. The research team of Jilin University found a new path for the formation of hexagonal diamond by graphite through the post-graphite phase at high temperature and pressure, and synthesized high-quality and nearly pure hexagonal diamond block materials for the first time. The hardness of this hexagonal diamond is 40% higher than ordinary cubic diamond, and the thermal stability is also better, and it can reach 1100℃ in a vacuum environment. This discovery opens up new directions for diamond selection and application, which may play an important role in the high-end industrial sector in the future.

For consumers, understanding the material selection of diamonds helps to make a more informed choice when buying diamonds. When purchasing diamonds, be sure to check the relevant certificates, such as GIA (Gemological Institute of America) certificate, IGI (International Gemological Institute) certificate, etc., these certificates are an important guarantee of diamond quality. At the same time, according to their own budget and needs, comprehensive consideration of carat weight, color, clarity and cutting factors, choose the most suitable for their own bright star.