things to know about our Popular gems

Gemstone information

        The sources for colored gemstones have changed dramatically in the last twenty-five years. Previously, most sapphire and ruby came from Thailand, Myanmar (Burma) and Sri Lanka (Ceylon) while Brazil was the primary source for most other colored stones. In Brazil's heyday, one couldn't walk the gem producing areas of Governador Valadares or Teofilo Otoni without dealers pushing massive quantities of gems at you. At that time, nearly all of the cut gems on the streets of Chanthaburi, Thailand were of Asian origin.

 

        Today, most quality colored gemstones are cut in Thailand with the majority being mined in East Africa. Twenty-five years ago, Thai dealers felt that African sourced gemstones were irrelevant, but with the discoveries in Ethiopia, Kenya, Tanzania, Mozambique and Madagascar, nearly 70% of gems cut in Thailand are from East Africa. Estimates are that about 80% of sapphire and ruby are now mined in East Africa and it is interesting to note that Sri Lanka (Ceylon), another important source, was actually connected to East Africa some 225 million years ago. Due to political and cultural conditions, it is almost impossible to determine the exact origin of many gemstone. 

 

We hope you will find this information informative and fun!

ALEXANDRITE

 

Color: Greenish in daylight to Reddish in incandescent light

Hardness: 8.5

Locations: Brazil, Mozambique, Russia, Tanzania

 

This stone was named after the Czar of Russia, Alexander II. It was discovered in the Ural Mountains of Russia on the ruler’s birthday in the early 1830’s. The gemstone became extremely popular in Russian jewelry and lead to the Ural mines being exhausted today. It is a June’s birthstone, but is also recognized to be a gift for the 55th wedding anniversary.

 

Alexandrite is a rare form of chrysoberyl and can change color in different lighting conditions. While other stones can also display changes in color, Alexandrite typically shows the most dramatic effect. In daylight, the stone has a vibrant green, blue-green, or a pastel green color. When viewed under incandescent light it displays a violet, ruby red, or purple color. This has led to the famous gem being described as “emerald by day, ruby by night.”

 

This stone is rarely found in sizes over 2.0 carats. Its value is based on the limited quantity in which it is found, its size, clarity, and quality of color change. To clean, use soapy water, alcohol, or commercial solvents. Ultrasonic or steam cleaners are safe.

 

 

GARNET: Tsavorite, Demantoid, Color Change, Rhodolite, Malaya, Spessartine & Almandine

 

Colors: Dark Red to Ruby Red, Reddish Orange to Orange, Brownish Orange, Pink, Purple, Green, Yellowish Green or Clear

Hardness: 6.5-7.5 (different garnet varieties will have different a hardness)

Locations: Canada, China, Czech Republic, Germany, India, Italy, Nigeria, Norway, Russia, South Africa, Sri Lanka, Tanzania, United States

 

Garnet is one of the few gem species that spans a broad spectrum of color, but it is best known for its shades of red. Most are surprised to learn that garnet is found in multiple hues of pink, purple, green, yellow, orange, and brown. It is January's birthstone and is also the suggested gift for the 2nd wedding anniversary. The name for garnet comes from the Latin derivative granatus, meaning seed, because it often resembles small round seeds when found.

 

While the garnet family contains more than a dozen varieties with a similar chemical structure, the majority of the garnet varieties can be classified as one or a mixture of five types: 

Almandine, the most common type, is dark red to brownish-red. 

Pyrope is a deep, vivid red. Fine quality Pyrope may be confused with a dark ruby, however medium-quality gems look much like Almandine.

Rhodolite, a blend of pyrope and almandine, is a light to dark pink to purplish red.  In order for a garnet to qualify as Rhodolite, however, its dominant hue must be purple. 

Andradite comes in yellow, green or brown, known as demantoid when emerald in color. 

Grossular garnet comes in yellow, orange and brown, known as Tsavorite in its green variety and hessonite when cinnamon colored.

Spessartine comes in shades from reddish brown to yellowish orange.

 

Lively, bright colors usually command higher prices in better qualities of garnet that are typically eye-clean. Rhodolite, particularly in its purple colors, and spessartite, in bright orangish red, are uncommon and considered more valuable, with the rarest garnets recognized as Tsavorite and Demantoid. The increasing scarcity of fine emerald has majorly contributed to Tsavorite’s popularity.

 

Garnets occur in relative abundance worldwide and enjoy widespread use. Today they mainly come from African countries, however garnet can also be found in India, Russia, and Central and South America. They form under high temperatures and pressures. Geologists can actually use garnets as an indication of the temperatures and pressures at which certain rocks were formed. Typically not enhanced, garnets need only warm soapy water and a soft brush to clean. An ultrasonic cleaner is safe for most varieties except andradite (Demantoid). Steam cleaners are not recommended. 

 

RUBY

 

Color: Red to Purplish Red

Hardness: 9

Locations: Afghanistan, Australia, Burma, Cambodia, India, Kenya, Madagascar, Pakistan, Sri Lanka, Tajikistan, Tanzania Thailand, Vietnam

 

Next to diamond, ruby is the second hardest gemstone, ideal for all types of jewelry, especially rings. With a name derived from the Latin word, rubeus, meaning red. Ruby is July's birthstone and is recognized as the traditional gift for the 15th and 40th wedding anniversaries. Besides their value as precious gems, rubies are also used extensively in laser technology.

This corundum varietal gem, sister to sapphire, only comes in one color. However, the shades of red in which it comes vary from purplish and bluish red to orangey red in medium to dark tones, but the trade term Pigeon’s Blood red is the universally recognized color for higher priced ruby. Color is key when considering value. Prized colors are pure red with no overtones of brown or blue. Better qualities are usually eye-clean. Ruby in sizes over 2.0 carats is difficult to come by. In its finest quality, any size is rare and can earn a higher price per carat at auctions than flawless diamonds.

Rubies are routinely enhanced by traditional heating methods to produce, intensify, or lighten color, and/or improve clarity. To clean ruby, use soapy water or commercial solvent and a brush. Mechanical cleaners are generally safe, but exercise caution as some ruby treatments may not be stable and will ruin the gem’s appearance upon contact with prolonged heat. 

 

SAPPHIRE

 

Color: Traditionally Blue, Sapphire can come in all colors of the rainbow

Hardness: 9

Locations: Australia, Burma, Cambodia, China, India, Madagascar, Nigeria, Sri Lanka, Tajikistan, Thailand, United States

 

Most commonly known for its shades of celestial blue, sapphire actually comes in almost every color of the rainbow. Sapphire, being a variety of corundum, is actually colorless when it is pure aluminum oxide.  Trace elements like iron and titanium give blue sapphire its timeless allure. Colors other than blue and ruby are typically referred to as “fancy sapphire.” Next to diamond and like ruby, sapphire is the second hardest gemstone, ideal for all types of jewelry, especially rings.

As September's birthstone, sapphire is also the preferred gift for the 5th and 45th wedding anniversaries. In fact, sapphire is a popular gem choice for brides who want to express their unique personality. Fans of sapphire engagement rings include Queen Elizabeth, Princess Anne, Princess Diana, Joan Crawford, Jean Harlow, Ivana Trump, Kirstie Alley and Debra Messing.

Although the name is derived from the Latin word for blue, sapphirus, sapphire is actually available in yellow, peach, orange, cognac, pink, violet, purple, and green, as well as colorless, white, gray and black. The more vivid the color of a natural sapphire, the greater the price it can command. Better quality sapphires are usually eye-clean and have a deep, clear blue color. Typically, sapphires over 2.0 carats are more difficult to find.

Sapphires are routinely enhanced by traditional heating methods and sometime diffusion to produce, intensify or lighten color and/or improve clarity. To clean sapphire, use soapy water or commercial solvent and a brush. Mechanical cleaners are generally safe.

 

SPINEL

 

Color: Red, Brown, Black, Green, Blue, Lavender and Grey

Hardness: 8

Locations: Afghanistan, Austrlia, Burma, Italy, Madagascar, Pakistan, Russia, Sri Lanka, Sweden, Turkey, United States

 

Centuries ago, in Sanskrit writings, spinel was called the daughter of ruby, adored yet somehow differently. The Crown Jewels of Great Britain are graced with spinel gems and have resided in the regalia of kingdoms throughout history. The origin of its name is uncertain. It is suspected to be derived from the Latin word spina meaning ‘spine’ or ‘thorn’, because it is often found as sharp crystals

Spinel comes in a variety of colors including orange, pink, blue, lavender, mauve, and vivid red. Much like rubies, spinel seem to fluoresce or glow in natural daylight. While common in sizes up to 2.0 carats, larger gemstones can also be acquired. The strongest reasons for buying spinel are its rich, brilliant array of colors and its attractive affordability.

Spinel is a durable gemstone that is perfect for all jewelry uses. It is most often faceted in oval, round or cushion shapes. Clean with mild dish soap.

 

ZOISITE: Tanzanite & Fancy Tanzanite

 

Color: Grey, Pink, Green, Blue, Yellow and Brown

Hardness: 6

Locations: Austria, Norway, Pakistan, South Africa, Sweden, United States

 

Zoisite was named after an Austrian scientist who discovered it in the Saulape Mountains of Austria. The blue variety of zoisite is called Tanzanite, displaying purple and sometimes green hues when viewed at different angles.  This beautiful optical phenomenon is referred to as pleochroism, which is defined a gem’s ability to display different colors when viewed at different angles.  

 

No recent discovery has had a greater impact on the gem market than Tanzanite. In 1967, a Portuguese prospector discovered the stone in Tanzania while looking for sapphire.

 

 A December birthstone, Tanzanite is recognized as the gift for the 24th wedding anniversary and also for the birth of a child - inspired by the native Mansai tradition of wearing blue beads and a fabric for a healthy and positive new life.

 

Zoisite occurs in various colors including yellow, golden-brown and green, and has been coined in the trade as “Fancy Tanzanite.” Fine Zoisite is typically eye-clean with good clarity. It is routinely enhanced by traditional heating methods to produce shades of violet blue to purple. To clean, use warm soapy water and a soft brush. Avoid ultrasonic and steam cleaners, and contact with chemicals.

 

TOURMALINE

 

Color: Deep Green, Violet, Black, Brown, Pink, Red, Blue and Colorless

Hardness: 7-7.5(different gemstones within this family will have different hardness)

Locations: Afghanistan, Brazil, Canada, Germany, Madagascar, Namibia, Pakistan, Russia and the United States

 

Perhaps the most diverse gemstone available, tourmaline possesses a dazzling array of colors. Moreover, there are bi-colored and tri-colored tourmalines where two or more colors appear side by side in the same gemstone.  This has also been coined in the trade as “Parti-colored.”

An October birthstone, tourmaline is also the chosen gift for the 8th wedding anniversary. Tourmaline, when heated or rubbed, acquires an electric charge that attracts small objects such as dust and hair. Because of Tourmaline’s electrical abilities, it is used in electrical devices and to make pressure gauges. 

 

The name derives from the Sinhalese term ‘turmali’ given to colored mixed crystals on the island of Sri Lanka. Different colored members of the group are given separate names, a few of them are:

 

Chromdravite, which is a dark green.

Indicolite can be found in an electric deep blue to blue green color.

Rubellite and watermelon tourmaline (Elbaite) are pink to deep red and green.

Siberite, which is a violet color.

 

Color determines price when it comes to Tourmaline, so the more vivid the color, the higher the price it will command. Tourmalines are commonly enhanced by traditional heating methods. To clean Tourmaline, use warm, soapy water or mild detergent. Avoid ultrasonic and steam cleaners. 

 

ZIRCON

 

​Color: Light Brown to Reddish Brown, Colorless, Grey, Yellow, Green and Blue

Hardness: 7.5

Locations: Australia, Brazil, Burma, Cambodia, Canada, France, Germany, Italy, Nigeria, Norway, Russia, Sri Lanka, Tanzania, Thailand, United States, Vietnam

 

This stone gets its name from the Arabic word ‘zargun’, meaning golden color. In addition to its popular gem-quality stones, Zircon is also used as a source of the metal zirconium and is now used in the production of nuclear reactors. This gemstone did not come into popularity in western countries until the 1920s; however, its luster and hardness make it a very popular stone for rings.

 

Zircon is available in several colors including yellow, orange and green, with blue, the most sought after, and brown most available. Brown zircon is commonly enhanced by traditional heating methods to produce red and blue colors, while yellow is occasionally heated to improve its color. Green zircon is not typically enhanced. Clear or transparent Zircon can be used as a simulant for diamond.

 

Zircon is widely distributed. The best source for gem-quality blue zircon is western Cambodia. Other popular sites include Burma, Sri Lanka, and Thailand. Deposits of zircon have also been found on the moon. To clean zircon, use warm soapy water and a soft brush. Avoid contact with chemicals. 

 

 

Source Reference: Oldershaw, Cally (2008).  Gems of the World.  Firefly Books Ltd. 2009.

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