December Birthstone – Turquoise, Blue zircon, Tanzanite

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Turquoise hardness is #5 to #6 on Mohs scale, and generally fair to good in toughness. Sources are China, Iran, and the US.

Turquoise is one of the world’s most ancient gems. Archaeological excavations revealed that Egyptian royalty wore turquoise jewelry as early as 5500 BC, and Chinese artisans were carving it more than 3,000 years ago. Turquoise is the national gem of Tibet, and has long been considered a stone that guarantees health, good fortune, and protection from evil.

Turquoise was a ceremonial gem and a medium of exchange for Native American tribes in the southwestern US. They also used it in their jewelry and amulets. The Apaches believed that turquoise attached to a bow or firearm increased a hunter’s or warrior’s accuracy. The gem’s name comes from the French expression pierre tourques or  “ Turkish stone” The name, which originated in the 13th century, reflects the fact that the material probably first arrived in Europe from Turkish sources.

Turquoise can be translucent to opaque, with a color that usually ranges from light to medium blue or greenish blue. It’s often mottled, and sometimes has splotches. It might also have veins of matrix running through it. The most valuable turquoise is an even medium blue, with no matrix, and the ability to take a good polish.

Turquoise is plentiful and available in a wide range of sizes. It’s used for beads, cabochons, carvings, inlays. Although well known to consumers, it popularity in the mainstream jewelry industry comes and goes. The biggest and most permanent market is in the American Southwest. It’s also popular elsewhere among people who are captivated by that region’s mystery and romance, as well as by the blue of its skies.

zircon

Zircon is #6 to #7.5 hardness on Mohs scale, and fair to good toughness, yet it can be brittle and might be easily abraded. Sources are Australia, Cambodia, China, Myanmar(Burma), Sri Lanka, Thailand, and Vietnam.

Most of us might have heard of Zircon, but never seen it. Mostly, this is because of colorless zircon’s wide use as a diamond simulate in the early 1900’s. It was long ago replaced in that role by more convincing look-alike, but its name still means “imitation” to many people. In the Middle Ages, this gem was thought to induce sound sleep, drive away evil spirits, and promote riches, honor, and wisdom. Many scholars think the stone’s name comes from the Arabic word zarkun, meaning “cinnabar” or “vermilion”. Others believe the source is the Persian word zargun, or “gold colored”. The most common color for the blue zircon on today’s market is a distinctive greenish blue that’s often called “blue zircon”. Others include green, yellow, orange, red, brown, and even purple. The colors are often light and muted, but the finest stones have strong, rich color.

Zircon is one of the few colored stones that might show visible dispersion. The supply of zircon is generally limited, and typical sizes depend on color. Blue or green stones normally range from 1 ct. to 10 ct., yellow and oranges up to 5 ct.. While reds and purples are usually smaller. Most colors are available in various fancy shapes, but colorless and blue stones are often fashioned in the style known as zircon cut—a round brilliant with eight extra facets around the culet. Heat treatments that produces many of its colors makes zircon brittle, for this reason, it’s safe to recommend zircon in earrings or pendants, or in protected ring settings. This will keep the gem from becoming scratched and abraded and make it less vulnerable to fracturing.

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Tanzanite is #6 to #7 hardness on Mohs scale, and fair to poor toughness due to cleavage and sensitivity to thermal shock. Source is Tanzania.

Tanzanite is relatively new to the colored stone galaxy. This transparent blue gem first turned up in 1962, scattered on the Earth’s surface in northern Tanzania, a country in eastern Africa. Scientist identified it as a variety of the mineral zoisite.  About five years later, a prospector discovered a large deposit of it in the same area, and serious mining began. Tiffany & Co. recognized its potential as an international seller and made a deal to become its main distributor. Tiffany & Co. named the gem after the country it came from, and promoted it with a big publicity campaign in 1968. Almost overnight, tanzanite was popular with leading jewelry designers and other gem professionals, as well as with customers who had an eye for beautiful and unusual gems.

Tanzanite’s public recognition and popularity have grown steadily, but there have been wide fluctuations in the gem’s supply and price level, due mostly to Tanzania’s volatile political, social, and economic conditions. Tanzania remains the gem’s only source, so the outlook for long-term availability is rather doubtful. Tanzanites are routinely heat-treated to produce colors that include light to dark violetish blue and bluish purple, as well as pure blue. Rich, deep hues are valued most, but usually are seen only in stones weighing 5 cts or more. This is mainly because of decisions made during the cutting process. Tanzanite typically shows pleochroism, which means it displays different colors from different directions. It usually looks violetish blue from some directions, purple from others. Predominately blue tanzanite is generally worth more per carat, but because of the way tanzanite crystals grow, a cutter can usually get a bigger stone by orienting the gem to show the purple color. While the trade considers the pure blue stones to be the “top” grade, some people actually prefer the lighter and more purplish colors.

Tanzanite is a special-care gem for two reasons: sensitive to thermal shock, and the potential for cleavage. Sometimes the temperature change between the hot lights of the display case and the chilly glass countertop in an air-conditioned showroom can be enough to develop cleavages in tanzanite. When looking for tanzanite jewelry, earrings and pendants are good choices for everyday wear. Tanzanite shouldn’t be handled carelessly.

November Birthstone – Topaz, Citrine

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Topaz is #8 on the Mohs scale, and toughness is poor due to cleavage. Sources are Australia, Brazil, Madagascar, Mexico, Myanmar(Burma), Namibia, Nigeria, Pakistan, Sri Lanka, and United States.

The topaz name came from Topazios, the old Greek name for an island in the Red Sea, now called Zabargad. The island never produced topaz, but it was once a source of peridot, which was confused with topaz before the development of the modern mineralogy. Some scholars trace the origin back to Sanskrit (an ancient language of India) and the word topas or topaz, meaning “fire”

The ancient Greek believed that topaz gave them strength. In Europe during the Renaissance (the period from the 1300’s to 1600’s), people thought that topaz could break spells and dispel anger. For centuries, many people in India have believed that topaz worn above the heart assures long life, beauty, and intelligence.

Topaz has an exceptionally wide color range that includes various tones and saturation of blue, green, yellow, orange, red, pink, and purple. Colorless topaz is another option. The color varieties are often identified simply by hue—blue topaz, pink topaz, and so forth—but there are also a couple of special trade names:

  • Imperial topaz—medium reddish orange to orange red. This is one of the most expensive colors.
  • Sherry topaz—yellowish brown or brownish yellow to orange. This term comes from the color of sherry wine. Stones in this color range are often called precious topaz to help distinguish them from the less expensive citrine and smoky quartz.

Most colors are available in standard faceted shapes, but the sizes differ from color to color. However, market availability varies according to color. Blue color topaz is abundant, size ranges from 1 ct. to 25 ct., and there’s usually plenty of sherry topaz range from 1 ct. to 10 ct. One might be able to find larger sizes in sherry or blue. Yet, the supply of imperial topaz, red, purple, and pink tends to be limited. Generally, red is the most valuable topaz color, but market prices and preferences vary from country to country. Imperial topaz brings the highest prices in Japan and Germany. Japanese buyers also favor pink topaz. The biggest market for blue topaz is in the US, where it provides a gem alternative that’s lower in cost and more intense in color than aquamarine. The biggest faceted gem ever recorded is topaz in the collection of the Smithsonian Institute.

 

citrine

Citrine, #7 on Mohs scale, is a quartz variety, and good in toughness. Sources are Bolivia, Brazil, Spain.

Citrine is the top-selling transparent gem in the yellow to orange color range. Its name was derived from the Latin word citrus, meaning “citron”, a fruit closely related to the lemon. This gem combines a warm attractive color with good wear-ability and a moderate price—an unbeatable combination for many people.

Citrine comes in an exceptional wide range of sizes. Most citrine is faceted in traditional rounds and fancy shapes, and you’ll also find it fashioned into more unusual cuts and carvings. Before the development of modern gemology, citrine was traditionally confused with topaz because of their similar colors.

October Birthstone – Opal, Tourmaline, Rose zircon

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Opal is ranked at #5 to #6.5 on Mohs scale and very poor to fair in toughness. Sources are Australia—black and white opal, Brazil—white opal, and Mexico—fire opal.

Opal is the world’s most popular phenomenal gem. Many cultures have credited opal with supernatural origins and powers. Arabic legends say it falls from heaven in flashes of lightning. The ancient Greeks believed opals gave their owners the gift of prophecy and guarded them from disease. Europeans have long considered the gem a symbol of hope, purity, and truth. In fact, throughout most of history, opal has been regarded as the luckiest and most magical of all gems because it can show all colors. Once, it was thought to have the power to preserve the life.

Opals had been divided into into many different categories, four of the main types are:

-Black opal-translucent to opaque with play of color against a black or other dark bodycolor. The industry supply of fine black opal is extremely limited.

-White opal- translucent to semitranslucent with play of color against a white or light gray bodycolor. White opals are generally available in a wide range of sizes.

-Boulder opal-translucent to opaque with play of color against a light to dark background. Host-rock fragments, or matrix, are part of the finished gem

-Fire opal-translucent to translucent with brown, yellow, orange, or red bodycolor. This material which often doesn’t show play of color is also known as Mexican opal, Gold opal, or Sun opal. Fire opals are available in a wide range of sizes just like white opals.

 

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Tourmaline is ranked #7 to 7.5 on the Mohs scale and has fair in toughness. Sources are Afghanistan, Brazil-major source, Kenya, Madagascar, Mozambique, Myanmar, Namibia, Pakistan, Russia, and United States.

 

People have probably used tourmaline as a gem for centuries, but until the development of modern mineralogy, they identified it as some other stone(ruby, sapphire, emerald, and so forth) based on its color. Portuguese explorers discovered deposits of green tourmaline in Brazil in the mid 1500s, but they thought it was emerald. The confusion about the stone’s identity is even reflected in its name, which comes from toramalli, which means “mixed gems” in Sinhalese (a language of Sri Lanka).

In the late 1800s, tourmaline became known as an American gem through the efforts of Tiffany gemologist George F. Kunz. He wrote about the tourmaline deposits of Maine and California, and praised the stones they produced. The supply of tourmaline began to expand during the first half of the twentieth century, when Brazil yielded some large deposits. Then in the beginning of the 1950s, additional finds appeared in countries around the world.

Tourmalines come in a wide variety of cool exciting colors. In fact, tourmaline has one of the most and widest color ranges of any gem species. It occurs in various shades of almost every hue, and there are a number of trade names for its color varieties:

*Rubelitte->pink, red, purple red, orangy red, or brownish red.

*Indicolite->dark violetish blue, blue, and greenish blue.

*Paraiba tourmaline->intense violetish blue, greenish blue, or blue from the state of Paraiba, Brazil. This Paraiba tourmaline was discovered in 1988.

*Chrome tourmaline->intense green. Much of this colored by vanadium, the same element that colors many Brazilian and African emeralds.

* Parti-colored tourmaline->tourmaline with more than one color. One of the most common combinations is green and pink, but many others are possible.

* Watermelon tourmaline->pink in the center and green around the outside. Crystals of this material typically have a pink core surrounded by green, and they are cut in slices. Some tourmalines also show chatoyancy. Cat’s-eye tourmalines are most often green, blue, or pink, with an eye that’s softer and more diffused than the eye in fine cat’s eye chrysoberyl. (above pear shape picture is Paraiba tourmaline).

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Rose zircon is #6 to 7.5 on the Mohs scale and has a fair to good toughness, yet it’s brittle and therefore sensitive to knocks and pressure , and can be easily abraded. Sources are Australia, Cambodia, China, Sri Lanka, Burma, Thailand, Vietnam.

Zircon indeed one of the most classic colored stones used in gemstone rings. The brighter deeper rose colored Rose Zircon gives  an alternative to tourmaline in both price and perfection of crystalline  structure. Zircon is a compound of oxides silicon and zirconium and fairly hard to be faceted to brilliant luster. Zircon has a high refractive index and strong dispersion and has great brilliance and intensive fire. The luster is vitreous to a brilliant sheen. Attractive Rose Zircon is available in a faint pink to a dark medium rose hue.

 

September Birthstone – Sapphire/Corundum

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Sapphire is usually #9 on Mohs scale, excellent in toughness, but with large fractures/inclusions, or some treatments, can be less durable. Sources are Australia, Cambodia, China, India (Kashmir), Kenya, Madagascar, Myanmar(Burma), Nigeria, Pakistan, Rwanda, Sri Lanka, Tanzania, Thailand, United States, Vietnam. India is a famous, historic source of fine blue sapphire, and production is now very limited. Transparent sapphires of all colors are most often faceted. Translucent to opaque material is usually cut into cabochons or used for beads. Corundum is very hard and tough, and can be used in any type or style of jewelry, and worn by just about any people.

For centuries, sapphire has been associated with royalty and romance. The association reinforced in 1981, when Britain’s Prince Charles gave a blue sapphire engagement ring to lady Diana Spencer. Until her death in 1997, Princess Di, as she was known, charmed and captivated the world. Her sapphire ring helped link modern events with history and fairy tales. In ancient Greece and Rome, kings and queens were convinced that the blue sapphires protected their owners from envy and harm. Sapphires symbolize heaven, and ordinary people thought the gem attracted heavenly blessings. In other times, people instilled sapphires with the power to guard chastity, make peace between enemies, influence spirits, and reveal the secret of oracles. Sapphire has always been associated the color blue. Its name came from the Greek word “sappheiros,” which probably referred to lapis lazuli.

In the trade, “blue sapphires” refer to stones ranging from very light to very dark greenish or violetish blue, as well as those in various shades of pure blue. Large, top-quality stones are rare, but blue sapphires in other sizes and grades are almost always available. Not all sapphires are blue, however. It’s a variety species, as ruby corundum or any corundum that doesn’t qualify as ruby is considered sapphire. Fancy sapphires, as they’re called, come in violet, green, yellow, orange, pink, purple, and intermediate hues. There are also partially colored sapphires that show a combination of different colors. Some stones exhibit the phenomenon known as color change, most often going from blue in daylight or fluorescent lighting, to purple under incandescent light. Sapphires can even be gray, black, or brown. Colorless sapphires were once popular diamond imitators, and in recent years they’ve staged a comeback as accent stones. Fancy sapphires are generally less available than the blue sapphires, and some colors are scarce. Especially in very small or very large sizes. Still, fancy sapphires create a rainbow of options for customers who like the romance associated with this gem, but who also want something out of the ordinary.

August Birthstone – Spinel, Peridot, Sardonyx

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Spinel is #8 on Mohs scale, good toughness. Sources are Cambodia, Myanmar(Burma), Sri lanka, Tanzania, Thailand. Myanmar is known for fine-quality pink and red spinels.

Spinel is a good candidate for the title of “History’s Most Underappreciated Gems.” Some Ancient mines that supplied gems for royal courts, from Rome to China, produced spinels. Yet, they were usually confused with better-known stones like ruby and sapphire.Spinels history dates back to the 1300’s, and it’s a central stone in the British Imperial State Crown.

Modern technology hasn’t helped spinel’s confused identity either. At least as far as the general public is concerned. This is largely due to the widespread use of synthetic spinel as an imitation for many other gems. Most customers don’t even know there’s a natural version of the stone. Limited availability also contributes to spinel’s lack of public recognition. Gem-quality material is typically transparent and faceted, but it’s hard to find in sizes larger than 5 cts.

Spinel’s color range includes violet, blue, orange, red, pink, and purple. Blue spinels are often grayish and subdued, but the best are a deep rich color. The reds can rival fine ruby. The vivid orange to orange-red stones merit their name—flame spinel. Some spinels show color change, usually turning from grayish blue in daylight or fluorescent light, to purple under incandescent light. Spinel is a hard, tough stone that’s suitable for daily wear in any type of jewelry.

 

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Peridot is # 6 ½ to 7 on Mohs scale, fair to good in toughness. Sources are Myanmar, Pakistan, United States.

Peridot has always been associated with light. The Egyptians called it the “gem of the sun.” Some believed that it protected its owner from terrors of the night, especially when it was set in gold. Others strung the gem on donkey hair and tied it around the left arm to ward off evil spirits.  Today, Arizona’s San Carlos Indian Reservation is the world’s most commercially important producer. Peridot is usually transparent. It comes in an attractive range of colors, from brownish or yellowish green, to greenish yellow. People will be attracted to the bright lime greens and more subdued olive greens of this lovely gem. This gem is relatively inexpensive and plentiful, and normally available in standard shapes and calibrated sizes, up to about 5 cts. Larger stones are also fairly easy to find. Tumbled and faceted peridot is used for bead necklaces and bracelets. They are often combined with gems in contrasting colors—amethyst, citrine, and pink tourmaline, to name a few. The word peridot comes from the Arabic faridat, which means “gem”. Most peridot was formed deep inside the Earth and was brought to the surface by volcanoes. Some has also come to the Earth in meteorites, but this extraterrestrial peridot is extremely rare, and you’re not likely to see it in a retail jewelry store. Mineralogists refer to the stone as olivine.

sardonyx-stone

Sardonyx is # 6 1/2 to 7 on Mohs scale and good in toughness. Sources are Brazil, Madagascar, United States, and Uraguay.

Sardonyx is a Chalcedony varieties characterized by straight, parallel bands of different colors. Sardonyx is similar to black onyx, known as red onyx to some people. Sardonyx’s colors range from dark brown to brownish orange or brownish red alternate with either white or black.

Since Greek and Roman times, Sardonyx have provided gem carvers with ideal materials for cameos and intaglios. The color banding allows the creation of carved designs that contrast dramatically with their backgrounds. Sardonyx is also known to be the healing stone and associate with luck and friendship, good fortune, romance, marriage, stamina, energy and creativity and also considered as a stone of protection and strength.

Sardonyx is inexpensive, plentiful and available in large sizes and also traditionally popular for beads, cabochons and tablets. Sardonyx is accepted as one of the US birthstones for August.

July Birthstone – Ruby/Corundum

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Ruby is a #9 on Mohs scale, usually excellent in toughness, but with certain treatments or large fractures/inclusions can be less durable. Sources are Afghanistan, Kenya, Madagascar, Myanmar (Burma), Sri Lanka (Ceylon), Tanzania, Vietnam, and Thailand. Thailand is the world center for treatment and wholesale trade and mine production of rubies and has been declining since 1990s. Myanmar is considered to produce the finest quality of rubies. Where Sri Lankan rubies are often lighter in tone than rubies from Myanmar(Burma) or Thailand.

The name Burma or Burmese ruby is practically synonymous with the fine-quality ruby. Political changes let to the renaming of the country as Myanmar. But many people in the gem trade still refer as Burma ruby when they talk about the source of the world’s most prized rubies.

The first Burmese mines were located in Mogok, and the production fluctuated through much of the post-World War II era. The famous Mogok mining area of Burma(now the Union of Myanmar) has been so heavily mined for so many thousands of years that evidence is so rare. Yet the caves were once so rich that it’s unlikely that the early cave dwelling, tool-wielding humans who lived there were not aware of the dazzling red corundum crystals around them.

It was ruby in its reddest state that inspired the notion that rubies could cure blood disorders or heal wounds. People from distant past swallowed rubies whole or break them apart or pound them into powder and put them into liquid or pastry mixture, which they then rubbed on their skin. According to thirteenth-century medical from India, rubies were believed to cure digestive disorders.

Today, most rubies come from Myanmar and Madagascar. The discovery of a rich deposit in Mong Hsu helped the country get back to the forefront of ruby producers. Ruby is the US birthstone for July.

June Birthstone – Alexandrite, Pearl, Moonstone

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Alexandrite is #8.5 on Mohs scale and has excellent toughness. Sources are Brazil, East Africa, Russia, and Sri Lanka. Alexandrite is a rare chrysoberyl variety with chameleon like qualities. Its color is a lovely green in daylight or fluorescent light, but it changes to brownish or purplish red in the incandescent light from a lamp or candle flame. Alexandrite’s dramatic color change is sometimes described as “emerald by day, ruby by night.’ Other gems also change color in response to a change in light source, but this gem’s transformation is so striking that the phenomenon itself is often called “The Alexandrite Effect”

Abundant alexandrite deposits were first discovered in 1830, in Russia’s Ural Mountains. Those first alexandrites were of very fine quality.They displayed vivid hues and dramatic color changes. The gem was named after the young Czar, Alexander II. It caught the country’s attention because its red and green colors mirrored the Imperial Russian flag. The spectacular Ural Mountains didn’t last forever, and now most alexandrite comes from Sri Lanka, East Africa, and Brazil. However, people can still find some of the famed Ural Mountain alexandrites in estate jewelry. They remain the quality standard for this phenomenal gemstone. The newer deposits contain some fine quality stones, but many possess less precise color change and muddier hues than the 19th century Russian alexandrites. Due to its scarcity, especially in larger sizes, alexandrite is a relatively expensive member of the chrysoberyl family. It shares its designation as June birthstone with cultured pearl and moonstone.

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Pearl is #2.5 to #4 on Mohs scale. Toughness is usually good, but variable due to aging, dehydration, and sometimes excessive bleaching during initial processing. Perhaps the best-loved gems of all time, their modern counterpart, cultured pearl, occur in a wide variety of colors. The most familiar colors are white and cream. The body color is often modified by additional colors called overtones, which are typically pink (called rose), green, purple, or blue, and some pearls show the iridescent phenomenon known as orient. Pearls are treasures from the Earth’s streams, rivers, lakes, seas, and oceans. They’ve always embodied the mystery, power, and life-sustaining nature of water. The spherical shape of some pearls also led to many cultures to associate this gem with the moon. In ancient China, pearls were believed to guarantee protection from fire and fire-breathing dragons. In Europe, they symbolized modesty, chastity, and purity. Pearl—natural or cultured—is a US birthstone for June together with alexandrite and moonstone. Cultured pearls are popular for bead necklaces and bracelets, or mounted in solitaire, pairs, or clusters for the use in earrings, rings, and pendants.

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Moonstone/Feldspar is #6 to #6.5 on Mohs scale, it’s poor in toughness because of its cleavage. Moonstone ranges from semi-transparent to opaque. It is most often find it in cabochons and carvings, set in rings and pendants, as well as the popular beaded necklaces and bracelets. It’s usually colorless, white, or light bluish gray with white or blue adolescence. Other colors include light green, yellow, brown, and sometimes gray to black. The market supply is normally steady in sizes up to about 25 cts, with large stones available in limited quantities.

May Birthstone – Emerald/Beryl

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#7.5 to #8 on Mohs scale, poor to good toughness. Sources are Colombia, Afghanistan, Brazil, Pakistan, Russia, Zambia. Colombia is one of the largest commercial producers of emeralds. Fine Colombian emeralds are highly regarded for their excellent color. Zambia, a major commercial source, as well. Zambian emeralds tend to have good clarity. Zimbabwe, the Sandawana Valley to be more specific, is also a famous source.

An emerald’s lush green color has soothed souls and excited imaginations since antiquity. Its name comes from the ancient Greek word for green, “smaragdus”. Rome’s Pliny the Elder, described emerald in his early encyclopedia, Natural History, which was published in the 1st century AD. His personal verdict reads “…nothing greens greener.” He described the use of emerald by lapidaries, who “have no better method of restoring their eyes than by looking at the emerald, its soft, green color comforts and removes their weariness and latitude.” Even today the color green is known to relieve stress and eye strain.

The first known emerald mines were in Egypt, dating back from at early 330 BC into the 1700’s. Emeralds, from what is now Colombia, were part of the plunder when 16th century Spanish explorers invaded the New World. Emerald is often mined and sold under peril—this natural resource, which Colombians cherish, is also coveted by underworld drug traders. The availability of fine quality emerald is limited. Emeralds were plagued in the late 1990s by negative publicity which stated that treatments were commonly used to improve its clarity. Emeralds are the most famous member of the beryl family. It was once believed to cure diseases like cholera and malaria. Its color reflects new spring growth, which makes it the perfect choice of a birthstone for the month of May. Its also the gemstone for the twentieth and thirtieth wedding anniversaries.

April Birthstone – Diamond

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Diamond scores #10 on the Mohs scale, and good is to excellent in toughness. Sources are South Africa, Australia, Brazil, Botswana, China, Canada, Ghana, Guyana, Indonesia, India, Namibia, Sierra Leon, Tanzania, Democratic Republic of the Congo, United States, Venezuela.  India was the world’s only major source until the 18th century. Then Brazil’s alluvial deposits were discovered in the 1700’s. Both countries were overshadowed by South Africa’s enormous primary deposits, which appeared in the late 1800’s.

Diamond and graphite are both made of carbon. Diamond is a metastable allotrope of carbon. The difference between diamond and graphite lies in the way their carbon atoms fit together. This is caused by the different pressure and temperature conditions that exist when either mineral is being formed.

In a diamond, the atoms are arranged in tight three-dimensional patterns, bonded more strongly in all directions than that of graphite’s atoms, which are bonded in layers. Only under the right temperature and pressure conditions can diamonds be formed. The best temperature and pressure exists in very limited areas of the Earth’s upper mantle, between 90 miles and 140 miles beneath the surface. At that depth, those ideal conditions work together to force carbon atoms to form the extremely strong bonds found in diamond crystals. Diamonds that exist today were delivered to the surface between 2.5 billion and 20 million years ago. Diamonds themselves can’t be dated. Researchers, published in 2010, indicated that youngest known diamonds found in Brazil were just about 107 million years old.

Diamonds are especially precious and rare. The typically color is yellow, brown, and gray to colorless (D,E,F). Other colors, blue, green, black, translucent, pink, violet, purple, red are considered fancy colored diamonds. These colored diamonds are extremely rare, making them priceless. Just to give you an idea, a 35.56 cts blue, fancy colored diamond, once belonging to the King of Spain, was sold at Christie’s Auctions for 24 million dollars.

March Birthstone – Aquamarine/Beryl

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#7.5 to #8 on Mohs scale, good toughness. Sources are Brazil (major source), Australia, China, Kenya, Madagascar, Mozambique, Nigeria (known for intense color under 5 carats), Pakistan, United States, and Zambia.

Aquamarine’s cool blue hues are reflected in its name, which comes from the Latin for “sea water” Medieval sages prescribed water touched by aquamarine for a host of ills, including those affecting the eyes and lungs. They promised the virtues of insight and foresight to the gem’s wearers.

Aquamarine crystals can grow to huge sizes, and are usually blessed with excellent clarity. Gem body colors range from greenish blue to blue-green in light tones. Usually, the color is more intense in large stones, but some aquamarine from Africa displays deeper blues in faceted stones of less than 5 carats. Brazil supplies the most aquamarine to the modern market.