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At Gemstoneindex you can find information on gemstones, minerals, jewelry, birthstones and more. It is intended as a guide to the beautiful and fascinating world of gemstones. Throughout history gemstones have been admired and worn as amulets and talismans; believed to have powers to protect against evil, disease, and as safeguards of health. Gemstones have…

A gemstone named after the country of Brazil, in which deposits were discovered for the first time in 1944. Presently, deposits are found in Minas Gerais in Brazil. At first it was incorrectly thought of as a chrysoberyl. Brazilianite is a sodium aluminum phosphate hydroxide. Brazilianite is a rare and beautiful crystal, much priced by…

Hematite or haematite takes its name from the Greek word haem for “blood,” which describes the color of its powdered form. Hematite is the most important iron ore because of its high iron content (70 percent) and its abundance. The steel-gray crystals and coarse-grained varieties with a metallic luster are known as specular hematite; the…

Zircon has been known since ancient times under various names. Zircon’s name most likely derives from the Persian word zargun for (“golden colored”). Zircon was also known in those times as hyacinth. Zircon comes in a variety of colors due to its prismatic to dipyramidal crystals, which can be colorless, yellow, gray, green, brown, blue,…

Unakite is a form of granite consisting of quartz, pink feldspar and green epidote. It is opaque but when polished it becomes a very attractive stone. Unakite’s name derives from the region where it was found, the Unaka mountain range in North Carolina, United States. Good quality unakite is considered a semi-precious stone; it will…

Turquoise’s name derives from the old French word pierre tourques, meaning “Turkish stone” because it was believed that the Persian (Iranian) stone was imported to Europe via Turkey. Turquoise forms as a porous blue cryptocrystalline aggregate and is found as encrustations, nodules, or botryoidal masses, or in veins within rocks in arid regions. Pure blue…

Tourmaline is a group of aluminoborosilicates, notably elbaite, dravite, schorl, and uvite. They crystallize as characteristic long prisms of triangular cross-section. Tourmalites are found in granites, pegmatites and quartz veins, and as an accessory in schists and gneisses. The true name for most gem tourmaline is elbaite, named for its type locality. Tourmaline was discovered…

Topaz is a high temperature mineral generally found in igneous rocks and high temperature veins. It is aluminum silicate fluoride hydroxide. Sodalite’s name comes from the Greek topazion, which may originate from the Greek topazin, which may originate from the Sanskrit tapas, meaning “fire,” or from the Egyptian island of Topazos (now Zebirget or St.…

Found in Tanzania deep within the Mererani mines, Tanzanite was first discovered back in the year 1967. This zoisite variety, which was first introduced by Tiffany & Co out of New York State, reflects the colors of a violet blue and happens to be quite a popular gemstone. Perhaps its most notable feature is it’s…