Gemological

Each diamond over 0.30 carats is accompanied by a diamond-grading certificate from the Gemological Institute of America, or Antwerp-based Diamond High Council HRD, or the International Gemological Institute.

Gemological identification A well-equipped gem testing laboratory can distinguish natural pearls from cultured pearls by using gemological X-ray equipment to examine the center of a pearl.

To research before you buy, he suggests the International Gemological Society (IGS) website.

Your purchase includes a gemological report and a Gem Trade Laboratory, Diamond Grading Report which outlines the characteristics of your new diamond when it was inspected at 10x magnification.

Swarovski’s man-made diamonds have the same physical and chemical composition as mined ones and are grown in a lab in California and certified by the Gemological Institute of America.

All their diamonds are ethically sourced and graded by the Gemological Institute of America (GIA).

Despite knowing the jewellery was worth much more than he had paid, the jeweller did not alert the authorities but sent the pieces to the Gemological Institute of America.

Although these may also be legitimately referred to as "pearls" by gemological labs and also under U.S. Federal Trade Commission rules, citation and are formed in the same way, most of them have no value except as curiosities.

Dopants are added to some manufactured rubies so they can be identified as synthetic, but most need gemological testing to determine their origin.

Electronic thermal probes are widely used in the gemological centers to separate diamonds from their imitations.

Gemological Institute of America.

Hofer, Stephen, Collecting and Classifying Colored Diamonds, p.414 In 1996, the Gemological Institute of America's Gem Trade Lab examined the diamond and, using their proprietary scale, graded it fancy deep grayish blue.

Industrial diamonds are valued mostly for their hardness and heat conductivity, with the gemological qualities of clarity and color being mostly irrelevant.

It has been described as the "most famous diamond in the world". citation Physical properties * Weight: In December 1988, the Gemological Institute of America 's Gem Trade Lab determined that the diamond weighed convert.

Special gemological techniques have been developed to distinguish natural diamonds, synthetic diamonds, and diamond simulants.

Synthetic emeralds are often referred to as "created", as their chemical and gemological composition is the same as their natural counterparts.

The gemological and industrial uses of diamond have created a large demand for rough stones.

Treated padparadschas may be very difficult to detect, and many stones are certified by gemological labs (e.