Education

Birthstones

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January - Garnet


Garnet is the name of a group of minerals that come in every color, except for blue, from the deep red of the pyrope garnet to the vibrant green of tsavorites. The most common colors are the beautiful variety of reds that range from a rust colored to a deep violet red.

The word “garnet” comes from the 14th century Middle English word gernet, meaning “dark red.” The word is derived from Latin granatum, which means “seed,” and is called so because of the gemstone’s resemblance to the beautifully red seeds of the pomegranate.

Garnet is a very durable gemstone (6.5-7.5 on the Mohs scale) found all over the world, including Wyoming, Czech Republic, Greece, Russia, Tanzania, Madagascar, Sri Lanka, and India. Mandarin Spessartite, tsavorite, and demantoid garnets are considered to be the most rare and expensive of all garnet stones.

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February - Amethyst


Amethyst is composed of quartz, which is the second most abundant material found in the Earth’s crust. Amethyst gets its color from irradiation, iron impurities and the presence of trace elements. Its hardness (a 7 on the Mohs scale) is the same as other varieties of quartz, which makes it a durable and lasting option for jewelry.

While amethyst is most commonly recognized to be a purple color, the gemstone can actually range from a light pinkish violet to a deep purple that can read more blue or red, depending on the light. Sometimes, even the same stone can have layers or color variants, so the way the gemstone is cut is important to the way the color shows in a finished piece.

Amethyst often occurs in geodes or in the cavities of granitic rocks. It can be found all over the world, including the United States, Canada Brazil and Zambia.

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March - Aquamarine


The serenely colored aquamarine invokes the tranquility of its namesake, the sea. In fact, the name aquamarine is derived from the Latin word aqua, meaning water, and marina, meaning the sea. Aquamarine is most often light in tone and ranges from greenish blue to blue-green; the color usually is more intense in larger stones, and darker blue stones are very valuable.

This gemstone is a variety of a mineral called beryl, which is the same mineral as emerald. Aquamarine grows in large, six-sided crystals that can be up to a foot long, making it a great gemstone to be cut and polished in larger carats for bold statement pieces. Large gemstones have been found all over the world, including one gemstone found in Brazil that weighed over 240 pounds. This gemstone is mined mainly in Brazil, but also is found in Nigeria, Madagascar, Zambia, Pakistan, and Mozambique

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April - Diamond


You may already know of diamond’s toughness, in fact, it’s the hardest gemstone and is made of just one element: carbon, that has been crystallized deep within the earth. Its structure makes it 58 times harder than anything in nature and can only be cut with another diamond.

Diamonds come in several colors, including yellow, red, pink, blue, and green, and range in intensity from faint to vivid. Generally speaking, the more saturated the color, the higher the value. In fact, diamonds sparkling with intense color are rare and may be priced higher than a colorless diamond of equal size. Because fancy-color diamonds are very desirable, color is sometimes introduced in a laboratory. These are correctly called color-treated diamonds.

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May - Emerald


Emerald, derived from the word “smaragdus,” means, quite literally, “green” in Greek. The deeper or more green an emerald, the more valuable it is. The rarest emeralds will appear to be an intense green-blue.

Like aquamarine, emerald is a variety of beryl, a mineral that grows with six sides and up to a foot in length. Emerald color can range from light green (though there is some argument whether these very light beryls are truly emeralds) to a deep, rich green. Emeralds are also like aquamarine in that the way the color is presents itself in jewelry depends on a good cut by a skilled gemologist.

Emeralds are found all over the world, including Colombia, Brazil, Afghanistan and Zambia. The availability of high-quality emerald is limited; consequently, treatments to improve clarity are performed regularly.

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June - Pearl


Pearls are the only gemstones made by living creatures. Mollusks produce pearls by depositing layers of calcium carbonate around microscopic irritants that get lodged in their shells.

Appropriately, the name “pearl” comes from the Old French perle, from the Latin perna meaning “leg,” referencing the leg-of-mutton shape of an open mollusk shell. Because perfectly round, smooth natural pearls are so uncommon, the word “pearl” can refer to anything rare and valuable.

The rarest and most expensive pearls are natural pearls made in the wild, without human interference. The majority of pearls sold today are cultured or farmed by implanting a grafted piece of shell (and sometimes a round bead) into pearl oysters or freshwater pearl mussels.

Pearls are very soft, ranging between 2.5 and 4.5 on the Mohs scale. They are sensitive to extreme heat and acidity; in fact, calcium carbonate is so susceptible to acid that authentic pearls will dissolve in vinegar.

Pearls used to be found in many parts of the world, but natural pearling is now confined to the Persian Gulf waters near Bahrain. Australia owns one of the world’s last remaining pearl diving fleets and still harvests natural pearls from the Indian Ocean. Today, most freshwater cultured pearls come from China. South Sea pearls are cultured along the northwestern coastline of Australia, the Philippines, and Indonesia.

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June - Alexandrite


A relatively modern gemstone, alexandrite was discovered in Russian emerald mines located in the Ural Mountains. Legends claim that it was discovered in 1834 on the same day that future Russian Czar Alexander II came of age, and was named to honor him.

Often described as “emerald by day, ruby by night,” alexandrite is a rare variety of the mineral chrysoberyl that changes color from bluish green in daylight to purplish red under incandescent light.

This chameleon-like color shift is the result of its uncommon chemical composition which includes traces of chromium, the same coloring agent found in emerald. The unlikelihood of these elements combining under the right conditions makes alexandrite one of the rarest and most expensive gemstones on earth and has a hardness of 8.5 on the Mohs scale.

The alexandrite mined from Russia’s famed deposits set the quality standard for this gemstone. Today most alexandrite comes from Sri Lanka, Brazil, and East Africa generally paling in comparison to the vivid colors of Russian gemstones.

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June - Pink Tourmaline


The name "tourmaline" comes from the Sinhalese words tura mali, which mean "stone of mixed colors." As its name implies, tourmaline stands apart from other gemstones with its broad spectrum of colors in every shade of the rainbow.

Tourmaline is not one mineral, but a fairly complex group of minerals with different chemical compositions and physical properties. Certain trace elements produce distinct colors, and many resulting varieties have their own names, for example black tourmaline known as “schorl” is rich in iron, which causes dark shades from deep brown to bluish-black and indicolite or blue tourmaline can appear purplish blue or bluish green, depending on the amount of iron and titanium.

Tourmaline is desirable because of its sheer range of color options and also with a good hardness of 7 to 7.5 on the Mohs scale.

Parti-colored tourmaline displays more than one color, due to chemical fluctuations during crystallization. A common color combination is green and pink. These are often cut in slices to reveal a red center surrounded by a green rim, earning the name “watermelon tourmaline.”

Tourmaline is mined in Brazil, Sri Lanka, Nigeria, Mozambique, Madagascar, Afghanistan, Pakistan and the U.S.—primarily Maine and California.

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July - Ruby


Ruby is the red variety of the mineral corundum, colored by the element chromium. All other colors of gem-quality corundum are called sapphire, which means color is key for this royal gemstone.

The chromium that gives ruby its red color also causes fluorescence, which makes rubies glow like a fire from within. Paradoxically, chromium is also what makes this gem scarce because it can cause cracks and fissures. Few rubies actually grow large enough to crystallize into fine quality gems, and these can bring even higher prices than diamonds.

Accordingly, the name “ruby” comes from rubeus, the Latin word for red. In ancient Sanskrit, ruby translated to ratnaraj, which meant “king of precious stones.” These fiery gems have been treasured throughout history for their color and vitality. Tough and durable, ruby measures 9 on the Mohs scale. Diamond is the only natural gemstone harder than ruby.

Burma’s Mogok Valley historically produced the finest ruby material, famous for its deep blood-red color with purplish hues. These Burmese Rubies, also called Pigeon’s Blood Rubies, command a premium over brownish or orange-tinged varieties from other regions. The Mong Hsu region of Myanmar began producing rubies in the 90's after discovering that heat treatment improved the color saturation. Other ruby deposits exist in Vietnam, Thailand, India, parts of the Middle East, East Africa and even the United States.

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August - Peridot


Peridot is the rare gem-quality variety of the common mineral olivine, which forms deep inside the Earth’s mantle and is brought to the surface by volcanoes. Rarely, peridot is also found inside meteorites.

Peridot’s signature green color comes from the composition of the mineral itself—rather than from trace impurities, as with many gemstones. That’s why this is one of few gemstones that only comes in one color, though shades may vary from yellowish-green to olive to brownish-green, depending how much iron is present.

Though peridot is widely recognized by its brilliant lime green glow, the origin of this gemstone’s name is unclear. Most scholars agree that the word “peridot” is derived from the Arabic faridat, which means “gem,” but some believe it’s rooted in the Greek word peridona, meaning “giving plenty.”

Peridot only measures 6.5 to 7 on the Mohs scale and of the world’s peridot supply comes from the San Carlos Reservation in Arizona. Other sources are China, Myanmar, Pakistan, and Africa.

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September - Sapphire


Although sapphire typically refers to the rich blue gemstone variety of the mineral corundum, this royal gemstone occurs in a rainbow of hues. Sapphires come in every color except red, which earn the classification of rubies instead.

Trace elements like iron, titanium, chromium, copper, and magnesium give naturally colorless corundum a tint of blue, yellow, purple, orange or green, respectively. Sapphires in any color but blue are called “fancies.” Pink sapphires tow a fine line between ruby and sapphire. In the U.S., these gemstones must meet a minimum color saturation to be considered rubies. Pinkish orange sapphires called padparadscha (from the Sri Lankan word for “lotus flower”) can draw higher prices than some blue sapphires.

The name “sapphire” comes from the Latin sapphirus and Greek sappheiros, meaning “blue stone,” though those words may have originally referred to lapis lazuli. Some believe it originated from the Sanskrit word sanipriya which meant “dear to Saturn.”

Sapphires are found in India, Myanmar, Thailand, Vietnam, Sri Lanka, China, Australia, Brazil, Africa, and North America (mainly Montana). Their origin can affect their value as much as color, cut, clarity, and carat size.

The remarkable hardness of sapphires, which measure 9 on the Mohs scale, is second only to diamond.

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October - Opal


The name “opal” originates from the Greek word opallios, which meant “to see a change in color.”

Opal’s characteristic “play-of-color” was explained in the 1960s, when scientists discovered that it’s composed of microscopic silica spheres that diffract light to display various colors of the rainbow. These flashy gemstones are called “precious opals;” those without play-of-color are “common opals.” Dozens of opal varieties exist, but only a few (like Fire Opal and Boulder Opal) are universally recognized. Opals are often referred to by their background “body color”—black or white.

Since opal was discovered in Australia around 1850, the country has produced 95 percent of the world’s supply. Opal is also mined in Mexico, Brazil, Honduras, Ethiopia, the Czech Republic and parts of the U.S., including Nevada and Idaho.

The water content of opal can range from three to 21 percent—usually between 6 and 10 in gem-quality material. This, combined with hardness of only 5.5 to 6 on the Mohs scale, makes opal a delicate gemstone that can crack or “craze” under extreme temperature, dehydration, or direct light.

The most valuable opals, known as black or gem opals, feature large, luminescent areas of one or more bright colors against a dark background. Opals are rarely treated to enhance their color, however they can be quite delicate and should not be exposed to steam cleaning or excess acids. The best cleaning method is with a soft damp or dry cloth.

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October - Pink Tourmaline


The name "tourmaline" comes from the Sinhalese words tura mali, which mean "stone of mixed colors." As its name implies, tourmaline stands apart from other gemstones with its broad spectrum of colors in every shade of the rainbow.

Tourmaline is not one mineral, but a fairly complex group of minerals with different chemical compositions and physical properties. Certain trace elements produce distinct colors, and many resulting varieties have their own names, for example black tourmaline known as “schorl” is rich in iron, which causes dark shades from deep brown to bluish-black and indicolite or blue tourmaline can appear purplish blue or bluish green, depending on the amount of iron and titanium.

Tourmaline is desirable because of its sheer range of color options and also with a good hardness of 7 to 7.5 on the Mohs scale.

Parti-colored tourmaline displays more than one color, due to chemical fluctuations during crystallization. A common color combination is green and pink. These are often cut in slices to reveal a red center surrounded by a green rim, earning the name “watermelon tourmaline.”

Tourmaline is mined in Brazil, Sri Lanka, Nigeria, Mozambique, Madagascar, Afghanistan, Pakistan and the U.S.—primarily Maine and California.

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November - Citrine


Citrine, is a variety of quartz that ranges from pale yellow to brownish orange in color. It takes its name from the citron fruit because of these lemon-inspired shades.

The pale yellow color of citrine closely resembles topaz, which explains why November’s two birthstones have been so easily confused throughout history.

Citrine’s yellow hues are caused by traces of iron in quartz crystals. This occurs rarely in nature, so most citrine on the market is made by heat treating other varieties of quartz—usually the more common, less expensive purple amethyst and smoky quartz—to produce golden gemstones.

Brazil is the largest supplier of citrine. Other sources include Spain, Bolivia, France, Russia, Madagascar, and the U.S. (Colorado, North Carolina, and California). Different geographies yield different shades of citrine. With a hardness of 7 on the Mohs scale, citrine is very durable against scratches and everyday wear-and-tear.

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November - Precious Topaz


Through much of history, all yellow gemstones were considered topaz and all "topaz" was thought to be yellow. Topaz is available in many colors, and it’s likely not even related to the stones that first donned its name.

The name topaz derives from Topazios, the ancient Greek name for St. John’s Island in the Red Sea. Although the yellow stones famously mined there probably weren’t topaz, it soon became the name for most yellowish stones.

Pure topaz is colorless, but it can become tinted by impurities to take on any color of the rainbow. Precious topaz ranges in color from brownish orange to yellow and is often mistaken for “smoky quartz” or “citrine quartz,” respectively—although quartz and topaz are unrelated minerals.

The most prized color is Imperial topaz, which features a vibrant orange hue with pink undertones. Blue topaz, although increasingly abundant in the market, very rarely occurs naturally and is often caused by irradiation treatment.

The largest producer of quality topaz gemstones is Brazil. Other sources include Pakistan, India, Sri Lanka, Russia, Australia, Nigeria, Germany, Mexico, and the U.S. — mainly California, Utah, and New Hampshire. Measuring 8 on the Mohs scale, topaz is a very hard and durable gemstone.

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December - Zircon


The name “zircon” likely comes from the Persian word zargun, meaning “gold-colored.”  Others trace it to the Arabic zarkun, meaning “vermillion.” Given its wide range of colors—spanning red, orange, yellow, green, blue, and brown—both origins are plausible.

Zircon commonly occurs brownish red, which can be popular for its earth tones. However, most gem-quality stones are heat treated until colorless, gold or blue (the most popular color). Blue zircon, in particular, is the alternative birthstone for December.

Color differences in zircon are caused by impurities, some of which (like uranium) can be slightly radioactive. These gemstones are also treated with heat to stabilize the radioactivity. While radiation can break down zircon’s crystal structure, it plays a crucial role in radiometric dating. Zircon, the oldest mineral on Earth, contains important clues about the formation of our planet. Though it measures 7.5 on the Mohs scale of hardness, its faceted edges can chip.

Zircon from Australia dates back 4.4 billion years. Australia still leads the world in zircon mining, producing 37 percent of the world’s supply. Other sources include Thailand, Sri Lanka, Tanzania, Cambodia, Canada, and the United States.

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December - Turquoise


Admired since ancient times, turquoise is known for its distinct color, which ranges from powdery blue to greenish robin’s egg blue. It’s one of few minerals to lend its name to anything that resembles its striking color.

The word “turquoise” dates back to the 13th century, drawing from the French expression pierre tourques, which referenced the “Turkish stone” brought to Europe from Turkey.

Ancient Persia (now Iran) was the traditional source for sky blue turquoise. This color is often called “Persian blue” today, regardless of its origin. The Sinai Peninsula in Egypt was also an important historical source.

The U.S. is now the world’s largest turquoise supplier. Nevada, New Mexico, California, and Colorado have produced turquoise, but Arizona leads in production by value, as well as quality. The stone’s popularity here makes it a staple in Native American jewelry.

Turquoise is found in arid regions where rainwater dissolves copper in the soil, forming colorful nodular deposits when it combines with aluminum and phosphorus. Copper contributes blue hues, while iron and chrome add a hint of green.

Some turquoise contains pieces of host rock, called matrix, which appear as dark webs or patches in the material. This can lower the stone’s value, although the uniform “spiderweb” pattern of Southwestern turquoise is attractive.

The hardest turquoise only measures 6 on the Mohs scale, which made this soft gemstone popular in carved talismans throughout history.

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December - Tanzanite


Tanzanite is the exquisite blue-purple variety of the mineral zoisite that is only found in one part of the world. Named for its limited geographic origin in Tanzania, tanzanite has quickly risen to popularity since its relatively recent discovery.

Zoisite had been around more than a century and a half before this rare blue variety was found in 1967. Trace amounts of vanadium, mixed with extreme heat, cause the blue-purple color—which ranges from pale blue to intense ultramarine with violet undertones.

Due to pleochroism, tanzanite can display different colors when viewed from different angles. Stones must be cut properly to highlight the more attractive blue and violet hues, and deemphasize the undesirable brown tones.

The majority of tanzanite on the market today is heat treated to minimize the brown colors found naturally, and to enhance the blue shades that can rival sapphire.

Tanzanite is still only found on a few square miles of land in Tanzania, near majestic Mount Kilimanjaro. Its price and availability are directly tied to mines in this region, most of which are now slowing production significantly. Tanzanite measures 6.5 to 7 on the Mohs scale of hardness—which is not nearly as hard as the sapphire it often substitutes.

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December - Blue Topaz


Topaz in its pure form it is colorless or white. Impurities are what cause variations in color.

Some believe that "topaz" is a Middle English word, which was acquired from the Old French word "Topace" and Latin "Topazus.”

8 on the Mohs scale

Topaz is an aluminum silicate that contains fluorine and hydroxyl. The presence of iron and chromium impurities causes variations in color, which ranges from pale yellow, brown and grey to pastels shades of green, violet and pink and the stone is an 8 on the Mohs scale. Topaz is often preceded by its color, for example Blue Topaz, Pink Topaz, Yellow Topaz, White Topaz, and Sherry Topaz.

The most common venues from where Topaz is mined are Germany, The Czech Republic, Italy, Norway, Sweden, Pakistan, Afghanistan, Japan and Brazil, at specific sites of Texas and Utah as well as in Mexico.