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GEMSTONE EDUCATION

GEMSTONE EDUCATION
GEMSTONES A-Z

A free informational reference guide to gemstones.

ALEXANDRITE

It’s the color-change variety of the mineral, chrysoberyl. Alexandrite is bluish green in daylight and purplish red under incandescent light, hard and durable.

Birthstone month: June.

ALEXANDRITE

AMBER

A fossilized resin, amber is the color of the burnished sun – orange or golden brown. Sometimes it traps and preserves ancient life, including insects. Amber is the birthstone for the Start Sign of Taurus.

AMBER

AMETHYST

A purple variety of the mineral quartz, amethyst often forms large, six-sided crystals. The name of the gem comes from a Greek word that means 'not drunk'.

Birthstone month: February.

AMETHYST

AMETRINE

Ametrine, one of the rarest types of transparent quartz, combines two colors: amethyst’s purple and citrine’s orange-to-yellow.

AMETRINE

AQUAMARINE

Blue to slightly greenish-blue variety of the mineral beryl. Crystals are sometimes big enough to cut fashioned gems of more than 100 carats.

AQUAMARINE

CITRINE

Citrine’s color comes from traces of iron. It’s perhaps the most popular purchased yellow gemstone and an attractive alternative for topaz and yellow sapphire.

CITRINE

DIAMOND

The hardest gem of all is made of just one element: carbon. A diamond is valued for its colorless nature and purity. Most diamonds are primeval—over a billion years old—and are formed deep within the earth.

Birthstone month: April.

DIAMOND

FANCY COLOR DIAMOND

Only 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.

FANCY COLOR DIAMOND

EMERALD

Emerald is the most valued variety of beryl. Spanish conquistadors, Inca kings, Moguls, and Pharaohs all desired to possess it. Today, the finest emeralds come from Africa, South America, and Central Asia.

Birthstone month: May.

EMERALD

GARNET

The garnet group of related mineral species offers gems of every hue, including fiery red pyrope, vibrant orange spessartine, and rare intense-green varieties of grossular and andradite.

Birthstone month: January.

GARNET

IOLITE

Known in the jewelry trade as iolite, this mineral is known as cordierite to geologists and mineralogists. Iolite is strongly trichroic, meaning that it shows three colors when viewed from different angles.

IOLITE

JADE

Prized by civilizations from ancient China to the Aztecs and Mayans of Central America, jade is crafted into objects of stunning artistry. It is known for its beauty and wide-ranging expressiveness.

Birthstone month: August.

JADE

KUNZITE

Trace amounts of manganese give this pink-to-violet variety of spodumene its feminine glow. Kunzite was only confirmed as a unique variety of spodumene in the early part of the twentieth century.

Birthstone month: September.

KUNZITE

LAPIS LAZULI

Lapis lazuli is a gemstone of the kind that might have come straight out of the Arabian Nights: a deep blue with golden inclusions of pyrites, which shimmer like little stars. Regarded as the stone of friendship and truth, lapis lazuli is an alternate birthstone for those born in December.

LAPIS LAZULI

MOONSTONE

Feldspar is prized for its billowy blue adularescence, caused by light scattering from an intergrowth of microscopic, alternating layers. It is the favored gem of many Art Nouveau jewelry designers.

Birthstone month: June.

MOONSTONE

MORGANITE

Like its cousins, emerald and aquamarine, morganite is a variety of the beryl mineral species. This gem gets its subtle blush when a trace amount of manganese makes its way into morganite's crystal structure.

Birthstone month: October

MORGANITE

OPAL

Opal’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.

Birthstone month: October.

OPAL

PEARL

Pearls are produced in the bodies of marine and freshwater mollusks, either naturally or cultured by people with great care. Lustrous, smooth, subtly colored pearls are jewelry staples, especially as strands.

Birthstone month: June.

PEARL

PERIDOT

Peridot is a yellow-green gem variety of the mineral olivine. Found as nodules in volcanic rock, occasionally as crystals lining veins in mountains of Myanmar and Pakistan, and occasionally inside meteorites.

Birthstone month: August.

PERIDOT

ROSE QUARTZ

Microscopic mineral inclusions cause the pink color and translucence of rose quartz. Well-shaped, transparent pink quartz crystals are rare. It is an irresistible addition to any jewelry wardrobe.

ROSE QUARTZ

RUBY

Traces of chromium give this red variety of the mineral corundum its rich color. The ruby has been long valued by humans of many cultures. In ancient Sanskrit, ruby was called ratnaraj, or 'king of precious stones'.

Birthstone month: July.

RUBY

SAPPHIRE

Sapphire’s breathtaking blues have captured our imagination and inspired designs. Ancient lore tells us that blue sapphire brought spiritual enlightenment, inner peace, wisdom, insight, and the discernment to choose what's right. It is September’s birthstone and celebrates the 5th and 45th wedding anniversary.

Birthstone month: September.

SAPPHIRE

SPINEL

Although 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.

Birthstone month: August.

SPINEL

SUNSTONE

Sunstone, a member of the feldspar group, can be orthoclase feldspar or plagioclase feldspar, depending on chemistry. Both can show aventurescence. "Sunstone" applies to the gem's appearance.

SUNSTONE

TANZANITE

Named for Tanzania, the country where it was discovered in 1967, tanzanite is the blue-to-violet or purple variety of the mineral zoisite. It’s become one of the most popular of colored gemstones.

Birthstone month: December.

TANZANITE

TOPAZ

Colorless 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.

Birthstone month: December.

TOPAZ

TOURMALINE

Tourmaline'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.

Birthstone month: October.

TOURMALINE

TURQUOISE

It is rare and valuable in finer grades and has been prized as a gem and ornamental stone for thousands of years owing to its unique hue. Turquoise occurs as veins or seam fillings and as compact nuggets.

Birthstone month: December.

TURQUOISE

ZIRCON

Colorless zircon is known for its brilliance and flashes of multicolored light, called fire. These zircon properties are close enough to the properties of diamond to account for centuries of confusion between the two gems.

Birthstone month: December.

ZIRCON