A rare, color-changing gem, alexandrite is an emerald green in daylight, but takes on a deep red hue when seen under incandescent lighting. Chromium ions in the crystal structure intensely absorb yellow light, causing the unique and impressive shift in the color spectrum.
Made famous in popular culture by Steven Spielberg’s Jurassic Park, amber is fossilized resin from trees dating back millions of years. With a warm yellow hue, amber can sometimes contain insects, leaves, and other organic matter in a kind of time capsule spanning eons. The history of such pieces, forged above ground instead of below, attracts science-oriented minds and those looking for a unique connection to the past.
Thought to be stained by tears of wine from the Greek god of intoxication Dionysus, Amethyst is the violet variety of quartz and the birthstone for February. While colorless quartz is found in nearly every corner of the earth, the amethyst variety is considerably rarer. It has long been thought to have healing powers, and gives its wearers cool-headedness and clarity.
Also known as trystine or bolivianite, ametrine is a combination of both amethyst and citrine. This unique quartz variant has zones of both purple and yellow or orange. Ametrine first made its appearance in Europe through a gift to the Spanish queen by a famous conquistador.
Ammolite is a biogenic gemstone, like pearl or amber, in that it is produced by biological processes. Ammolite is made up of the fossilized shells of now extinct ammonites, shelled sea creatures that used to thrive in the oceans of North America. With iridescent spectral colors, ammolite makes an exciting addition to any jewelry piece.
Aquamarine is a blue variety of beryl, found in places like Sri Lanka, Madagascar, Columbia, Zambia, and the United States. This gem comes in a variety of shades, from light and airy turquoise to a dark blue variety called maxixe, which is much rarer.
The parent mineral of such varieties as aquamarine and emerald, beryl is made up of hexagonal crystals that can range from small deposits to formations several meters in size. Pure beryl is colorless, but natural variances bring out colors like green, blue, yellow, and red.
Another parent gemstone with many children, chalcedony is a form of silica with a waxy, translucent appearance. Chalcedony has been used as far back as the Bronze Age to carve seals and other important artifacts, and many of its variants were also widely used along trade routes through Central Asia.
A brilliant green gem, chrome diopside may not have the most elegant sounding name, but is one of the only stones capable of matching the allure of emerald. Affordable without compromising showmanship, chrome diopside is rich enough in color to make it unusable in large sizes as it becomes nearly opaque.
The parent gem of alexandrite and cymophane, chrysoberyl is a strong, durable stone with a characteristic yellow-green hue. Discovered in 1790 by one of the most outstanding geologists of the time, Abraham Gottlob Werner, chrysoberyl is actually unrelated to the beryl gem, but because of this frequent confusion this unique geological occurrence is often overlooked in its own right.
A variety of chalcedony, chrysoprase has a characteristic apple-green hue and is composed of ultra-fine crystals that cannot be distinguished under normal magnification. Whereas other green gems including emerald and chrome diopside gain their green color from the presence of chromium, chrysoprase enjoys its spectral brilliance thanks to trace amounts of nickel.
A rare natural variation of quartz, citrine exhibits a warm yellow coloring ranging from pale to a deep orange hue. Strong and durable, citrine is an excellent choice for jewelry, where its translucent brilliance catches wandering eyes. Citrine’s coloring comes from small particles of iron embedded within the quartz, which oxidizes and gives citrine its characteristic lemon (in French, “citron”) color.
Another biogenic gem, coral comes from colonies of marine invertebrates whose exterior shell, made of calcium carbonate, can be fashioned into jewelry and other ornaments. The most popular coral gemstone is red coral, which exhibits a durable pink or red skeleton. Found mainly in the Mediterranean Sea, red coral is extremely soft, and is often made into beads.
One of the only gemstones formed within a living organism, pearls have an iridescent, milky quality that the ancient Chinese associated with the power of the moon. Pearls are formed when mantle tissue in a mollusk is damaged, and nacre is secreted into the wounded area until it eventually hardens into a sphere.
Carbon is the basic building block of all life, and so has strong ties to the transitory world of growth and decay. When arranged in a unique lattice structure, however, carbon becomes one of the hardest materials known to man and a symbol of the eternal – diamond. Diamond has very few impurities and a brilliance nearly unmatched in any other gemstone.
The traditional birthstone for May, emerald is one of the most sought-after and highly valued gemstones. A variety of beryl, emerald is colored green by small amounts of chromium within its crystal structure. Mined by the ancient Egyptians, emeralds were brought to Europe en masse when 16th century Spanish explorers discovered the large collections of the Inca and Aztec civilizations.
Garnet
Named after the Greek word granatum, or seed, garnet is typically found as a deep red color that resembles the small seeds of a pomegranate, but can also exhibit the full spectrum of colors. Blue garnet, another color-shifting gem, shifts from blue green in daylight to purple under incandescent lighting thanks to the presence of vanadium.
Iolite
Coming from the Greek work for violet (ios), iolite is a relatively little-known bluish-purple gem that is perfect for those seeking a great value with compromising beauty. Iolite, also known as “Vikings Compass,” was used by the explorers to determine the location of the sun on cloudy days by using the gem as a polarizing filter.
Jade
For over 7,000 years, jade has been revered by royalty, warriors, and craftsman for its strength and beauty. Spanning civilizations from Chinese empires to the Mayans in Central America, jade is often associated with harmony and balance because of its cool, milky green appearance.
Kunzite
Kunzite, a pink colored gemstone, was only recently discovered in 1902 and was named after noted mineralogist and Tiffany & Co’s chief jeweler, George Frederick Kunz. First unearthed in Connecticut, Kunzite has since been found all over the world in places like Brazil, Afghanistan, and Madagascar.
Lapis Lazuli
This exquisite blue mineral has been mined for over 5,000 years, with artifacts containing the precious gemstone unearthed in Afghanistan, Sumeria, Siberia, and Egypt. Known as sapphire to ancient cultures, its brilliant color led to its use as a pigment in oil paint up until the 19th century.
Moonstone
Thought to be frozen rays of moonlight by the ancient Romans, moonstone’s calm, milky sheen has been associated with lunar deities for thousands of years. The blue shimmering variety of this precious gem typically come from mines in Sri Lanka, but many variations have been found in locations all over the world.
Morganite has a variety of other aliases, including “pink beryl,” pink “emerald,” “rose beryl” and others. After its initial discovery in 1910, large deposits of morganite were found in California in the United States, leading gemologists to name the precious stone after its most probable buyer in the region – banking mogul J.P. Morgan.
This unique form of chalcedony is best known for its black and white banded coloring, but can come in many different hues spanning the color spectrum. Black onyx is particularly striking, with its deep ebony color making for interesting accent pieces for modern jewelry.
Opal
The national gemstone of Australia, where more than 95 percent of this precious stone is found, opal has a unique coloring reminiscent of neon flames or perhaps a brilliant sunset in the Outback. Containing hues from many other gemstones, opal contains small spheres of silica that refract light in a unique and mesmerizing play of colors.
Peridot
Peridot is the birthstone of August, and comes in an iconic olive green. Another favorite of the Egyptians, peridot gems enjoyed a spectacular resurgence of interest in the 1990’s after a major find in Pakistan was unearthed.
Many gemstones are phenomenal gems, meaning they possess a distinct optical quality that gives rise to one of several phenomena of light. One such phenomenon is the asterism, or star-like pattern, which appears as rays across the domed surface of a given gemstone.
Ruby
The deep red fire of these precious gems have made rubies one of the most soughtafter pieces in history, noted in ancient religious texts and recorded in the histories of kings, pharaohs, and emperors. One of the four precious stones, ruby is in league with emerald, sapphire, and diamond.
Sapphire
Another member of the corundum family, sapphire is the name given to all color variants except red (ruby). The most well-known hue, however, is a brilliant blue. Because they are transparent and extremely hard (second only to diamond), sapphires can be used in a variety of applications from electronics to scientific instruments.
Spinel
Often mistaken for ruby, spinel is actually more rare but not as valuable as the popular red gemstone. Spinel can be found in pastels of pink, orange, purple, and blue. A hard and durable gemstone, spinel is commonly used as a replacement for ruby or sapphire for jewelry.
A variety of feldspar, sunstone is closely related to moonstone, and not just for their celestial nomenclature. It is often confused, however, with adventurine, a type of quartz, as sunstone’s actual name is adventurine feldspar. Though the two come from different minerals, both share the property of aventurescence, or a spangled optical effect.
Found only in the foothills of Mount Kilimanjaro in Tanzania, this mineral exhibits stunning hues of violet, sapphire blue, and burgundy. Called “the gemstone of the 20th century,” tanzanite was only discovered with the last half century, and was vigorously mined for only a few years before the mines were nationalized by the Tanzanian government.
One of the most historically-cited gemstones, topaz can come in a variety of colors including blue, orange, yellow, red, pink, blue, and clear. While blue topaz is the most popular, the golden-yellow imperial topaz is quite rare and remains the most sought after variety.
Ancient Egyptians thought that tourmaline, on its long journey up from the earth’s core, crossed through rainbow and gained all its extraordinary colors. While this may be somewhat inaccurate scientifically, it’s a tempting explanation to why this gem comes in so many stunning varieties and hues.
The famous sky-blue of turquoise is one of the oldest and most popular gemstone varieties in the world. Mined for thousands of years, turquoise have been prized by civilizations from all corners of the globe, including the ancient Egyptians, Aztecs, North American Indians, and others.
Zircon
Celebrated since the Middle Ages, Zircon comes in an array of colors, including blue, green, red, yellow, brown, orange, and clear. Because of its similarity to zirconia, a synthetic diamond, zircon is relatively unknown and misunderstood natural gemstone.