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A hand-held flashlight reveals the green color of a rough emerald from the Coscuez Emerald mine in Colombia. Photo by Eric Welch/GIA. Emerald is the green to bluish green variety of beryl, a mineral ...

One of the greatest concerns with emerald filling is the degree of clarity enhancement such treatment represents. Stones that appear to have excellent clarity with the unaided eye are often revealed ...

An aquamarine crystal in its natural state shows why these specimens are prized for their beauty. - Courtesy Daniel Trinchillo, Fine Minerals International Aquamarine is the green-blue to blue variety ...

This amethyst crystal is from Namibia. It shows classic quartz crystal shape: a six-sided columnar crystal with a pyramid-shaped termination at the top. Courtesy Daniel Trinchillo, Fine Minerals ...

Fancy color diamonds are among the rarest and most valuable gemstones. Diamonds in the normal color range are colorless through light yellow and are described using the industry’s D-to-Z color-grading ...

Figure 1. The GIA 7 Pearl Value Factors system classifies pearls according to size, shape, color, luster, surface, nacre, and matching. Composite photo by GIA staff. Prized by many cultures throughout ...

A brooch from the Victorian era features an oval citrine with six ruby accent stones. - GIA & Tino Hammid People have used quartz in jewelry for thousands of years. Egyptians gathered ornately striped ...

Online courses and Lab classes required to earn your online credential offered via the GIA Online Division are listed below. Click here to download the requirements ...

Antique Pyrope Hairpin in the collection of the Smithsonian National Museum of Natural History - Chip Clark, courtesy Smithsonian Institution Thousands of years ago, red garnet necklaces adorned the ...

The Robert Mouawad Campus at GIA World Headquarters in Carlsbad offers world-class gem studies with advanced classrooms, a renowned lab, and an iconic museum.

Just over a century ago, in the summer of 1912, a workman’s pickaxe struck through the floor of an old tenement house in Cheapside, a commercial district near the renowned St. Paul’s Cathedral in ...