Gemstones of the World—A to E
A colorful, brief background on the major gemstones used in jewelry today. Each gem includes a description, a photo of the crystal, and then cut gems.
Green in sunlight, red in lamplight — color-changing alexandrite is nature’s magic trick. It’s the color-change variety of the mineral chrysoberyl. Bluish green in daylight, purplish red under incandescent light, it’s hard and durable. Top quality examples are rare and valuable.
Amber is nature’s time capsule dispayed in colors of the burnished sun — orange or golden brown. This fossilized tree resin contains remnants of life on earth millions of years ago. It might trap and preserve ancient life, including insects, leaves, even scorpions and occasionally lizards. (What do you see in the sample below?)
Amethyst, the purple variety of the mineral quartz, often forms large, six-sided crystals. It is the essence of the color purple and beautiful enough for crown jewels, yet affordable enough for class rings. Fine velvety-colored gems come from African and South American mines.
One of the rarest types of transparent quartz, ametrine combines two colors: amethyst’s purple and citrine’s orange-to-yellow, growing together in a single, stunning crystal.
Named after seawater, aquamarine’s fresh watery hue is a cool plunge into a refreshing pool. It is the blue to slightly greenish-blue variety of the mineral beryl. It’s crystals are sometimes big enough to cut fashioned gems of more than 100 carats.
Citrine is the transparent, pale yellow to brownish orange variety of quartz. Its color comes from traces of iron. Citrine is perhaps the most popular and frequently purchased yellow gemstone and an attractive alternative for topaz or yellow sapphire.
Diamonds are among nature’s most precious and beautiful creations. The hardest gem of all, it is made of just one element: carbon. 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 DIAMOND
With dazzling brilliance and captivating color, the planet’s most valued gems are fancy colored diamonds. Fine color diamonds are the most rare and costly of all gemstones. Their ranks include the world’s most famous jewel—the Hope—and the most expensive gem ever auctioned—The Graff Pink.
Emerald is the bluish-green to green variety of beryl, a mineral species that includes aquamarine. As the most valued variety of beryl, emerald was once cherished by Spanish conquistadors, Inca kings, Moguls, and pharaohs. Today, fine gems come from Africa, South America, and Central Asia.
Check back next month for the next edition of Gems of the World G to P.
(Courtesy of gia.edu.)