A diamond examined in the Carlsbad lab shows chameleon coloring in an unusual pattern.

For the first time, wurtzite is found as an inclusion in gem material.

Irradiated CVD-grown diamonds are examined in the Carlsbad lab.

Crassostrea virginica, the so-called Eastern or American oyster, is a commercial seafood widely distributed along the east coast of the United States to the Gulf of Mexico.

Over the last decade, the production methods used to create synthetic diamond melee have improved substantially, along with the quality of the specimens themselves.

Projects developed by the GemHub to benefit miners, cutters, and others involved in the gem and jewelry industry.

Lotus Gemology receives submissions of star stones on a regular basis, so when we first saw the specimen shown here, it appeared to be one among many of our usual stones to test.

An unusual assembled stone is examined at GIA’s New York lab.

A black star sapphire produced from eastern Thailand, showing both golden and silver rays, is studied at GIA’s Bangkok lab.

Aesthetically pleasing inclusions are found in topaz from Pakistan’s Shigar Valley.

Gold: Vortex, Virtues, and Values was hosted by Initiatives in Art and Culture (IAC) at Bohemian National Hall in New York City, April 12–13. Now in its eighth year, the conference has become an annual industry gathering for those looking to evaluate the market, discover exceptional work, and discuss key gold-related issues.

A look at the color zoning exhibited by the largest HPHT-treated blue diamond graded by GIA.

Rare pearls, along with their shell, are studied in the Hong Kong lab.

Summarizes data collected on more than 15,000 natural blue/gray/violet diamonds examined by GIA during the last decade and examines the mechanisms that produce this color range.