Gemstone Education
Gemstone Education
Gemstones A-Z
A free informational reference guide to gemstones
AlexandriteThe color-changing variety of the mineral, chrysoberyl. In daylight, the mineral appears bluish-green. Under incandescent light, it appears purplish-red; hard and durable.
AmberFossilized resin with a golden-brown color. Amber sometimes traps and preserves ancient life forms, including insects.
AmethystPurple variety of the mineral quartz. Often forms large, six-sided crystals. The birthstone for February. The name of the gem comes from a Greek word that translates to: "not drunk."
AmetrineAmetrine, one of the rarest types of transparent quartz, combines two colors: amethyst’s purple and citrine’s orange-to-yellow.
AquamarineBlue to slightly greenish-blue variety of the mineral beryl. Crystals are sometimes large enough to fashion gems of more than 100 carats.
CitrineCitrine’s color comes from traces of iron. It’s perhaps the most popular purchased yellow gemstone and an attractive alternative to topaz and yellow sapphire.
DiamondThe hardest gem of all. It’s valued for its colorless nature and purity. Most diamonds are primeval—over a billion years old—and form deep within the earth.
Fancy Color DiamondOnly one in every 10,000 diamonds possesses natural color and is referred to as a fancy color diamond. They are purchased almost exclusively for the intensity and distribution of the diamond's color.
EmeraldThe most valued variety of beryl, emerald was once cherished by Spanish conquistadors, Incan kings, Moguls, and pharaohs. Today, these fine gems come from Africa, South America, and Central Asia.
GarnetThe garnet mineral species offers gems of every hue, including fiery red pyrope, vibrant orange spessartine, and rare intense-green varieties of grossular and andradite.
IoliteKnown as cordierite to geologists and mineralogists. Iolite is strongly trichroic, meaning that it shows three colors when viewed from different angles.
JadePrized by civilizations such as ancient China and the Aztecs, jade is often crafted into stunning artistic pieces. Beautiful and wide-ranging expressiveness.
KunziteA violet variety of spodumene. Trace amounts of manganese give this pinkish gem its feminine glow. Kunzite was only confirmed as a unique variety of spodumene in the early part of the twentieth century.
Lapis LazuliLapis lazuli is a gemstone that could have come straight out of the Arabian Nights: a deep blue with golden inclusions of pyrites which shimmer like little stars. Stone of friendship and truth.
MoonstoneFeldspar prized for its billowy blue adularescence, caused by light scattering from an intergrowth of microscopic, alternating layers. Favored gem of many Art Nouveau jewelry designers.
MorganiteLike its cousins emerald and aquamarine, morganite is a variety of the beryl mineral species. This gem gets its subtle blush from a trace amount of manganese that makes its way into the morganite’s crystal structure.
OpalOpal’s microscopic arrays of stacked silica spheres diffract light into a blaze of flashing colors. An opal’s color range and pattern help determine its value. Legend says that it is especially good for the eyes.
PearlProduced in the bodies of marine and freshwater mollusks naturally or cultured by people with great care. Lustrous, smooth, subtly-colored pearls are jewelry staples.
PeridotYellow-green gem variety of the mineral olivine. Found as nodules in volcanic rock, occasionally as crystals lining veins in mountains of Myanmar and Pakistan. They are also occasionally found inside meteorites.
Rose QuartzMicroscopic mineral inclusions create the pink color and translucence of rose quartz. Well shaped, transparent pink quartz crystals are rare. This gem is an irresistible addition to your jewelry wardrobe.
RubyTraces of chromium give this red variety of the mineral corundum its rich color. Long valued by humans of many cultures. In ancient Sanskrit, ruby was called ratnaraj, or “king of precious stones.”
SapphireDepending on their trace element content, sapphire varieties of the mineral corundum might be blue, yellow, green, orange, pink, purple or even show a six-rayed star if cut as a cabochon.
SpinelAlthough frequently confused with ruby, spinel stands on its own merits. Available in a striking array of colors, its long history includes many famous large spinels still in existence.
SunstoneSunstone, a member of the feldspar group, can be an orthoclase feldspar or a plagioclase feldspar, depending on its chemistry. Both can show aventurescence. It is given the name “Sunstone” for the gem’s appearance.
TanzaniteNamed for Tanzania, the country where it was discovered in 1967, tanzanite is the blue-to-violet variety of the mineral zoisite. It gas become one of the most popular colored gemstones.
TopazColorless topaz treated to blue is a mass-market gem. Fine pink-to-red, purple, or orange gems are one-of-a-kind pieces. Top sources include Ouro Prêto, Brazil, and Russia’s Ural Mountains.
TourmalineTourmaline's name comes from the Sinhalese word "turmali", which means "mixed". Occurring in more colors or combinations of colors than any other gemstone, tourmaline lives up to its name.
TurquoiseRare and valuable in finer grades, turquoise has been prized as a gem and ornamental stone for thousands of years owing to its unique hue. Turquoise occurs as vein or seam fillings, and as compact nuggets; these are mostly small in size.
ZirconColorless zircon is known for its brilliance and flashes of multicolored light. These zircon properties are close enough to the properties of diamond to account for centuries of confusion between the two gems.
