Learn About Stones
The essence of the color purple, amethyst is beautiful enough for crown jewels. Purple variety of the mineral quartz, often forms large, six-sided crystals. Fine velvety-colored gems come from African and South American mines.
Named after seawater, aquamarine’s fresh watery hue is a cool plunge into a refreshing pool. Blue to slightly greenish-blue variety of the mineral beryl. Crystals are sometimes big enough to cut fashioned gems of more than 100 carats. Well-formed crystals might make superb mineral specimens.
Chalcedony is a variety of the mineral quartz that appears in a large number of colors including blue, lavender, white, buff, light tan, gray, yellow, pink, red or brown. It is considered by some, a sacred stone and also a healing stone.
Diamonds are among nature’s most precious and beautiful creations. This hardest gem of all 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
Dazzling brilliance. Captivating color. The planet’s most valued gems are fancy color 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. 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.
Garnets are a set of closely related minerals forming a group, with gemstones in almost every color. 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.
Jade is actually two separate minerals: nephrite and jadeite. In China jade is the “stone of heaven”. Prized by civilizations from ancient China to the Aztecs and Mayans of Central America, jade is crafted into objects of stunning artistry.
Labradorite has unique characteristics. It turns sea blue, green and gold in bright light and grey or dark green color if viewed in dim light. It is a variety of feldspar which is found in igneous rocks. It is believed to bring joy, kindness and good fortune.
A ghostly sheen moves under the surface of this feldspar, like moonlight glowing in water. Feldspar 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.
Morganite is the pink to orange-pink variety of beryl, a mineral that includes emerald and aquamarine. 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.
Fireworks. Jellyfish. Galaxies. Lightning. Opal’s shifting play of kaleidoscopic colors is unlike any other gem. 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.
Perfect shining spheres. Lustrous baroque forms. Seductive strands, warm to the touch. Pearls are simply and purely organic. Produced in the bodies of marine and freshwater mollusks naturally or cultured by people with great care. Lustrous, smooth, subtly-colored pearls are jewelry staples, especially as strands.
Found in lava, meteorites, and deep in the earth’s mantle, yellow-green peridot is the extreme gem. 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.
Ruby is the most valuable variety of the corundum mineral species, which also includes sapphire. Traces 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.”
The name “sapphire” can also apply to any corundum that’s not ruby, another corundum variety. Depending 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.
The Black Prince’s Ruby. The Timur Ruby. For centuries, spinel, the great imposter, masqueraded as ruby in Europe’s crown jewels. 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.
Lush blue velvet. Rich royal purple. Exotic tanzanite is found in only one place on earth, near majestic Kilimanjaro. 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.
Honey yellow. Fiery orange. Cyclamen pink. Icy blue. In warm or cool tones, topaz is a lustrous and brilliant gem. 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.
Tourmalines have a variety of exciting colors with one of the widest color ranges of any gem. Comes in many colors, including the remarkable intense violet-to-blue gems particular to Paraíba, Brazil, and similar blues from Africa. Favorite of mineral collectors.
Azure sky, robin’s egg blue: Vivid shades of turquoise define the color that’s named after this gem. Ancient peoples from Egypt to Mesoamerica and China treasured this vivid blue gem. It’s a rare phosphate of copper that only forms in the earth’s most dry and barren regions.
Zircon is a colorful gem with high refraction and fire that’s unfairly confused with cubic zirconia. Optical properties make it bright and lustrous. Best known for its brilliant blue hues; also comes in warm autumnal yellows and reddish browns, as well as red and green hues.
Many thanks to the Gemological Institute of America for providing this content.