sapphire

Streak testing is a destructive gemstone test rarely used by gemologists, but it is a standard diagnostic test for mineralogists. Most gems leave…

Richard Hughes has been a leading ruby expert for decades. Learn how he got started and his tips for newcomers to the world of rubies.

Although pearls are one of humanity’s most ancient gems, natural undersea beds of pearl-producing oysters now occur very rarely. Cultured…

You’ll find gem cutting acronyms like L/W in faceting guides. Learn what these frequently used terms mean and how they can save gem cutters time…

Väyrynenite is a very rare mineral. Crystals as well as faceted gemstones in reddish, pinkish, and orange colors are prized collector’s items.…

Made from two or more materials, assembled gems can make durable and affordable jewelry. Learn more about gemstone doublets, triplets, and other…

An assembled gemstone is constructed from two or more combined materials. Gemstone doublets and triplets, intarsias, and rhinestones are all…

Some beautiful gems, like pearls, opals, and tanzanites, are very vulnerable to impacts and scratches, especially when worn on rings. Even more…

Even though diamonds make elegant and durable gems, you may find two stones that look alike. In contrast, no two opals look alike. Their beauty is…