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GIA reports represent the highest standard of reliability, consistency and integrity. And now, GIA Report Check is available for all GIA reports, providing you with an additional level of assurance.

Microscopic mineral inclusions are responsible for the gem's mysterious haziness. The color of rose quartz ranges from very light pink (almost white) to medium-dark pink. The most appealing color ...

Diamonds, colored stones, and pearls submitted to GIA laboratories today will have services completed and be ready for return by the estimated dates noted below. Requesting additional services after ...

The GIA Gem Trade Laboratory (GIA GTL) presents the system it uses to color grade faceted colored diamonds, and the information on which it is based. This system involves a trained grader establishing ...

Studies carried out at the DTC Research Centre have shown that single-crystal CVD synthetic diamond is clearly distinguishable from natural diamond. This article presents information about the CVD ...

GIA laboratory-grown diamond services include an overall quality assessment for laboratory-grown diamonds. The GIA assessments for laboratory-grown diamonds have a distinct format to fully ...

Figure 1. These 20 completely non-nacreous pen pearls, from the group of 22 samples in this study, are set against a pen shell displaying both nacreous (left) and non-nacreous areas (right). Photo by ...

In 1983, the Argyle mine was established as the first major diamond-mining operation in Australia. Almost immediately, it became the world’s largest source of diamonds in terms of the volume (carats) ...

Figure 1. Sapphires from a variety of sources. Faceted stones (left to right): 6.36 ct pink/orange (padparadscha), 1.63 ct pink, 4.76 ct violet, 5.43 ct violet purple, 3.03 ct blue, 2.12 ct blue, 8.06 ...

For the first time ever, the famous Hope diamond was graded by a widely recognized system. Although the 45.52-ct weight was confirmed, the GIA Gem Trade Laboratory graders found the clarity—recently ...