GIA developed this guide so retailers can use fluorescence tests to help identify gems right in their own stores.

Colored Stone Identification & Origin Report An Identification Report, with geographic origin added. For polished, loose or mounted natural alexandrite, emerald, jade, Paraíba tourmaline, red spinel, ...

Natural citrine is rare, and today most citrine quartz is the result of heat treatment of amethyst quartz. Even so, gems from the Victorian era have surfaced, and it’s not hard to imagine that citrine ...

A guide describing frequently encountered gem treatment processes, their detection, and special care tips for treated gems.

Stability Alexandrite is stable under normal wearing conditions, which means it’s resistant to the effects of heat, light, and common chemicals. Cleaning Warm, soapy water is always safe for cleaning ...

Mention of the name morganite immediately brings to mind beautiful pastels of pink, purplish pink, and orangy pink. - Robert Weldon, courtesy Mayer & Watt, Maysville, Kentucky Morganite is known ...

The world’s love of diamonds had its start in India, where diamonds were gathered from the country’s rivers and streams. Some historians estimate that India was trading in diamonds as early as the ...

This 3.74-ct. princess-cut aquamarine’s prized medium-blue color is highlighted by the 22 diamonds that surround it. The ring is an original, copyrighted design by Zoltan David. - Robert Weldon, ...

Fine amethysts have been set in religious jewelry and royal crown jewels for ages. It was once considered equal in value to ruby, emerald, and sapphire.

Alexandrite’s pleochroism makes it a challenge for cutters. When fashioning alexandrite, cutters orient the gem to show the strongest color change through the crown. It’s crucial to position the rough ...

GIA Knowledge Sessions, a series of talks and seminars that promise to engage participants in the most diverse and pressing issues in gemology today, including gemstone origin, laboratory-grown stones ...

Rose quartz is a quartz variety that gets its name from its delicate pink color which ranges from very light (almost white) to medium-dark.