Gemstone Directory
I would like to thank my unknown source of this table, I downloaded most of it several years ago
without keeping the source's information. I have added and edited the original, but the bulk was
coppied directly from an unknown source. THANK YOU!
Turquoise is out of alphabetic order and will take you to off this table and to my Turquoise info page.

Agate

Alexandrite

Turquoise 

Amethyst

Aquamarine

Carnelian

Chrysoberyl

Citrine

Diamond

Emeralds

Garnet

Jade

Lapis

Moonstone

Opal

Pearl

Peridot

Rubies

Sapphires

Spinel

Tanzanite

Topaz

Tourmaline

Zircon

 

 

Agate

Colors: Most colors

Refractive Index: 1.54 - 1.55

Durability: Fairly tough, can crack or chip

S.G.: 2.65 - 2.91

Material: Quartz

Treatment: Dyeing

Hardness: 7

Availability: Abundant

Localities: Brazil, Egypt, Germany, India, Italy, Japan, Madagascar, Mexico, USA & many more

Price: Low

Common Shapes: Cabochons, beads & cameos

 

Interesting Facts

Said by the ancients to render the wearer invisible, Agate has been admired by humanity for thousands of years. Its beauty and durability have prompted man to use it in both practical and ornamental forms.

 

One of the more outlandish uses is binding an Agate to each horn of your oxen to ensure a good harvest. The danger here is that your appropriately agated beasts of burden may then become invisible and a little hard to find.

 

In 1709 a Brazilian priest planned to use agates as antigravity devices on an air ship he had designed.

 

Agate is believed to cure insomnia, ensure pleasant dreams, protect from danger, promote strength, healing and a bold heart. Wearers become temperate, continent and cautious. Agate is a cooling stone; it reduces fever, quenches thirst, quiets the pulse and heart throbs and ensures good health and a long and prosperous life.

Agate is formed in a unique way and many fossils are actually agatized material that has replaced the original organic substance. For example, petrified wood is fossilized wood that has had its organic matter replaced by agate.

The main conditions necessary for agate formation are the presence of silica from devitrified volcanic ash, water from rainfall or ground sources, manganese, iron and other mineral oxides that form the bands and inclusions.

 

Characteristics

Agate is a fine-grained fibrous variety of Chalcedony Quartz and comes in many different forms ranging from transparent to opaque. Varieties include Blue, Blue Lace, Crazy Lace, Green, Indian, Moss, Tree, and Wood. Most popular are: Blue lace agate which has swirly white bands in a blue background; moss agate is so named for its moss-like pattern; fire agate is a brown-bodied stone containing yellow, green, and orange spots, with an iridescent shimmer like opal.

 

Evaluation

As there are so many varieties of agate, it is largely up to the buyer to determine its value. Most agate is in the low price range but some picture stones, carvings and unique pieces may command higher prices. The popularity of fire agate has increased in recent years, as has its price.

Ocean Jasper®
New Rock Discovery!

New discoveries brought to market are usually new deposits of an already known material. It is rare indeed that a really new material is found. Ocean Jasper fits the description of a truly new jasper.

Rhyolite is an igneous rock, rich in silica. As it cools, sometimes the silica starts to precipitate out of the magma, forming little spherical balls. This type of formation is easily recognizable in the aforementioned jaspers. If these balls or "globs" of silica-rich magma are allowed to grow larger before the whole mass becomes solid, they can crack and shrink forming what later may become Thundereggs.

Ocean Jasper has a typical rhyolite formation except that the entire mass has somehow been converted to pure silica (agate, jasper, quartz). The descriptions "silicated rhyolite", petrified rhyolite, or agatized rhyolite are non-sensical but take on a generally understandable meaning when viewing this rock. To my knowledge, there has never been a material like this available before.

The Name -- Ocean Jasper® The material is characterized as an orbicular jasper. That is because whenever a rhyolite has been found with enough silica in it to be polished, it has been sold as a jasper. Thus the rhyolite patterns have been associated with the word "jasper".

Ocean Jasper is an agate by the standard definition (agate being translucent and jasper being opaque). Ocean Jasper is rarely opaque. It was decided to call the material a jasper because rhyolitic patterns have been associated with the jasper category in the past and because "jasper" is listed as the mineral resource in the mining claims owned by Madagascar Minerals.

The word "Ocean" comes mainly from the location at the edge of the sea, along the northwest coast of Madagascar where the deposit was found. The forms in the rock itself are also suggestive of the bubbling surf of the sea.

 

 

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Alexandrite

Colors: Green & violet red color change

Refractive Index: 1.74 - 1.76

Durability: Tough

S.G.: 3.5 - 3.8

Material:Chrysoberyl

Treatment: None

Hardness: 8.5

Availability: Very rare

Localities: Brazil, Sri Lanka & Russia

Price: Low/moderate to very expensive

Common Shapes: Ovals, rounds & cushions

 

Interesting Facts

Alexandrite is one of the world’s most exotic and rare gemstones. By day, it resembles the “green fire” of emeralds, and by night, it takes on the glowing red luster of rubies. Alexandrite was first discovered around 1830 on the birthday of Czar Alexander of Russia, which it was named after. It is truly a gem suited for a Czar, as it contains the two royal colors of Russia, red and green.

 

The world’s major source of alexandrite is in the state of Minas Gerias, Brazil. In 1987, at the Lavra de Hematita mine, the world’s largest deposit of alexandrite was found. Russia was once one of the major sources of alexandrite; however, today, the Russian deposits are nearly depleted due to heavy mining. In 1993, another source of this extraordinary gemstone was found near the Tanzania-Mozambique border.

 

Characteristics

 

Color change is not unique to only alexandrite; however, the extremity of the color change in this gemstone surpasses all others. When alexandrite is viewed under daylight or fluorescent light, its color is that of medium to bluish green; however, when it is observed under incandescent light, its color is that of violet red. Alexandrite is quite tough. Its hardness is only transcended by those ofcorundum-based gemstones, such as rubies, sapphires and of course diamonds. Alexandrite can also occur in a cat’s-eye form, but it is exceptionally rare. In its finest quality, the gemstone should be semi-transparent with a sharp exhibition of the white eye.

 

Evaluation

The degree of color change is the first and most important consideration when evaluating the value of alexandrines. Low quality stones will present a less dramatic change of color, partially retaining some of the green color or appearing brown under incandescent light. The evaluation of alexandrite should be performed in a dark room under a single light source (i.e. a candle or a light bulb).

 


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Amethyst

Colors: Pale to dark violet

Refractive Index: 1.54 - 1.55

Durability: Fairly tough

S.G.: 2.65 - 2.91

Material: Quartz

Treatment: Heating

Hardness: 7

Availability: Abundant in many sizes

Localities: Brazil, India,Australia, Zambia, Uruguay & many more

Price: Low

Common Shapes: Everything is possible

 

Interesting Facts

 

Amethyst is one of the most common gemstones available and has been popular since Pre-Roman times. The wine-loving Greeks believed that amethyst prevented intoxication while medieval European soldiers wore amethyst amulets as protection in battle.

Amethyst is actually a form of Quartz – one of the most common substances on earth. Tiny amounts of iron and aluminum turn ordinary clear quartz into amethyst.

All forms of quartz (including amethyst) are piezoelectric, making for important applications in electronics. Tourmaline is the only other gemstone that possesses this property.

 

The term "Siberian" amethyst refers to a high grade of stone that is no longer commercially produced. Most of the high-grade amethyst mined today is in Uruguay, southern Brazil and Africa.

 

Characteristics

Amethyst ranges from pale to dark violet. The finest qualities of amethyst are a medium dark violet with a strong secondary red color. Darker shades of amethyst may display slight color fluctuations under different light sources.

 

Amethyst of all qualities is available in all sizes and shapes. Light amethyst will be very low in per carat prices while even the finest qualities are still very reasonably priced. Darker amethyst of any size will have color zoning. This may not be visible without extensive examination. Often the zoning consists of areas of red violet and areas of blue violet, this combination can enrich the appearance of the stone. However, sometimes the zoning is easily visible and detracts from the beauty of the stone. If the zoning is unsightly the value is lessened.

 

Evaluation

Amethyst is the most expensive variety of quartz. Uniformity of color and intense, deep color commands the highest price. Any color zoning or inclusions diminish the price. The highest grade will flash red and pink throughout the gem.

 


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Aquamarine

Colors:Blue

Refractive Index: 1.56 - 1.59

Durability: Slightly fragile to tough

S.G.: 2.67 - 2.84

Material: Beryl

Treatment: Heating

Hardness: 7.5 – 8

Availability: A variety of sizes

Localities: Brazil, Nigeria & Madagascar

Price: Low to very expensive

Common Shapes: Emerald cuts, ovals & cushions

Interesting Facts

 

For many centuries, oceanic energy was believed to be contained within the delicate semblance of aquamarines. When amulets made of this precious gem were worn, sailors believed that unmatched bravery would be instilled into their souls, giving them the power to overcome even the most powerful storm.

Brazil was previously the world’s major supplier of aquamarines; however, today, African nations, such as Nigeria and Madagascar, provide a greater supply of this gemstone.

 

Characteristics

 

Aquamarines are often eye-clean, and any inclusions within this blue gemstone can easily be seen. A variety of sizes are readily available, and as the size increases, the color of aquamarines tends to intensify.

 

Evaluation

The intensity of color and the clarity of the stone are the most important criteria when evaluating this captivating blue stone. Deep blue aquamarines are rare and command higher prices in the world’s gemstone markets.


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Carnelian

Colors: Orange, red, brown

Refractive Index: 1.54 - 1.55

Durability: Fairly tough

S.G.: 2.65 - 2.91

Material: Quartz. Silicon Dioxide with Iron impurities

Treatment: Heating, dyeing

Hardness: 6.5 - 7

Availability: Abundant in many sizes

Localities: Brazil, India, Japan, Uruguay, USA & many more

Price: Low

Common Shapes: Beads, cabochons & cameos

Interesting Facts

Fit for a queen. An ancient Sumerian queen at that! Carnelian has been an important gem in nearly every great civilization the world has ever seen. From the royalty of Ur – the Mesopotamian capital of pre-biblical times, to Napoleon and Tibetan Buddhists, Carnelian has been revered for its healing, spiritual and creative qualities.

Also known as Sadoine or Mecca Stone and sometimes spelt Cornelian, the name Carnelian is derived from Carne, the Latin for flesh, due to the stone’s coloring.

A deeply religious stone, Carnelian was used by the Egyptian goddess Isis to protect the dead on their journey through the afterlife; it is the symbol of the Apostle Philip; was one of the stones on Aaron’s breast plate of judgment (Exodus: xxviii, 15-30); and Muhammad’s seal was an engraved Carnelian set in a silver ring. To this day Buddhists in China, India and Tibet believe in the protective powers of Carnelian and often follow the Egyptian practice of setting the stone with turquoise and lapis lazuli for enhanced power.

 

Carnelian is recommended for those with bad memories, creative blocks, befuddled minds, weak voices and a lack of courage. It is said to be beneficial in treating impotence, infertility, insomnia, menstrual cramps, neuralgia, rheumatism, asthma, bad blood,lethargy, digestive problems, and skin conditions like acne and psoriasis in both humans and animals. Carnelian also helps hotheaded people overcome anger and establish self-control, and it even protects the wearer from envy and falling objects.

Carnelian is the national gemstone for Norway and Sweden.

Characteristics

 

Carnelian is a translucent orange to red variety of chalcedony. The red tints are caused by iron oxide impurities. It is most commonly made into beads, cabochons, and carvings.

 

Evaluation

As carnelian is fairly common, it is an inexpensive gem. The best carnelian is translucent. Some carnelian will be dyed. Carnelian is often carved and the quality of carving is a key issue in determining price.

 

 


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Chrysoberyl

Colors: Yellow, yellowish green, green, brown, violetish red & greenish-blue color change

Refractive Index: 1.74 - 1.76

Durability: Tough

S.G.: 3.5 - 3.8

Material: Beryllium Aluminum Oxide

Treatment: None known

Hardness: 8.5

Availability: Alexandrite & cat’s eye very rare. Yellows & greens available

Localities: Brazil, Burma, India, Sri Lanka, Russia, Ural Mountains & Zimbabwe

Price: Low/moderate to very expensive

Common Shapes: Ovals, rounds & cushions

 

Interesting Facts

Encompassing such unusual features as color-change and chatoyancy, the chrysoberyl family is an enigmatic category of gemstones ranging from very inexpensive to top-drawer prices.

There are three principal varieties of chrysoberyl:

Alexandrite and cymophane (cat’s eye) are well known and among the most expensive of all gemstones. Ordinary faceted chrysoberyl is equally rare and beautiful, yet is one of the least expensive stones. All varieties are exceptionally tough, producing some extremely durable gems.

The name chrysoberyl is derived from the Greek for golden (chryso) and green gemstone (beryl). The color ranges from yellow to green to brown. When cut, ordinary chrysoberyl is an extremely brilliant stone, ideal for everyday wear and it is anticipated that it will be one of the next “new” products to become fashionable in the jewelry industry in the near future.

Chrysoberyl is said to assist in striving for excellence, bring peace of mind and increase self-confidence. It also promotes kindness, generosity, benevolence, hope, optimism, renewal, new beginnings, compassion and forgiveness. This stone expresses springtime, youth and innocence.

Chrysoberyl is said to enhance the healing properties of other stones, and to treat disorders of the pancreas, liver and kidneys.

 

Characterisitics

 

Ordinary transparent chrysoberyl is most often yellow, yellowish green, or brown in color. The color in yellow chrysoberyl is due to iron (Fe+3) impurities. When well cut, it produces bright, durable gems that, while not often seen in jewelry, are attractive and relatively affordable.

 

Cat’s-eye chrysoberyl is a translucent gem ranging in color from a honey yellow or honey brown to yellowish green to an apple green. It is known for its reflected light effect called “chatoyancy.” This is achieved by cutting stones that have very small, parallel “silk” inclusions into cabochons (dome shapes, not faceted). As the gem is rotated, it exhibits a distinct, silvery white line across its dome that seems to open and close like a cat’s eye.

 

 

Evaluation

The most desired stones are brilliant yellows, greens and occasionally oranges. The browner a chrysoberyl is, the less valuable.

Faceted stones over 10 carats are rare, over 20 carats extremely hard to obtain, and clean stones over 30 carats are museum pieces.

 

Fine cat's-eyes may be yellow, yellowish green, or golden brown. In the finest qualities, the gems will be semi-transparent and they will exhibit a sharp white eye. As you turn the stone around, the eye will move. The best cat's-eyes also exhibit a "milk and honey effect," when the stone is rotated, one side of the stone appears transparent, as the other side takes on a creamy appearance. In large cat's-eyes, the milk and honey effect is an important consideration in valuing the stone. Cat's-eyes are always cut into cabochons.

 

Sri Lanka and Brazil produce the most chrysoberyl cat's-eyes. This stone is an excellent choice for men. It has a masculine appeal and it is very durable. A fine quality stone will be in the expensive range.

 

 


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Citrine

Colors: Yellow, orange, red

Refractive Index: 1.54 - 1.55

Durability: Fairly tough

S.G.: 2.65 - 2.91

Material: Quartz.

Treatment: Presume heating

Hardness: 7

Availability: Abundant in many sizes

Localities: Brazil

Price: Low

Common Shapes: Everything is possible

 

Interesting Facts

One of the most affordable gemstones on the market, citrine is a golden yellow form of quartz which takes its name from "citron," the French for lemon.

 

In former times citrine was used as a protective talisman against the plague, bad skin and evil thoughts, and as a charm against snakebites and other venomous reptiles. It is also believed to symbolize happiness, aid digestion, remove toxins from the body, and be useful in the treatment of depression, constipation and diabetes.

 

Citrine is one of the accepted birthstones for November, as well as the anniversary gemstone for the 13th year of marriage. It is found mainly in Brazil.

 

Characteristics

Citrine does appear naturally but most commercial citrine is the result of heating amethyst. Colors range from pale yellow to yellowish-brown and “Madeira” red, after the color of the wine. Traditionally the Madeira shades were valued higher but these days many people prefer the bright lemony shades that mix better with pastel colors.

Since most citrine starts out as amethyst that is heated to turn its color to gold, citrine jewelry should be kept away from prolonged exposure to strong light or heat. With this precaution, citrine jewelry will last for many generations.

 

Evaluation

Citrine is readily available, very affordable in large sizes and stands up well to daily wear. Citrine can be easily confused with topaz and has even been called “topaz quartz.” This is incorrect and should be watched out for.

 

 

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Diamond

Colors: Clear, yellow, brown, pink, blue, green, lavender, orange & red

Refractive Index:\2.42

Durability: Tough but has perfect cleavage, protect from blows

S.G.:3.52

Material: Carbon

Treatment: None common. Laser drilling and filling (fracture filling), irradiation and heating to produce fancy colors

Hardness: 10

Availability: Strong supply in colorless to tinted yellow in stones up to five carats

Localities: Angola, Australia, Botswana, Canada, China, Congo, Namibia, South Africa, Russia & Zaire

Price: Expensive

Common Shapes: Round, marquise, pear, oval, heart,emerald,radiant,princess,trilliant & more

Interesting Facts

The hardest, rarest, densest natural substance known to man, diamonds have been a source of fascination (and misinformation) since 800 BC when they were first presented to royalty in India. In those days the Indians believed that diamonds were created when lightning struck rock and the sub-continent was the only producer of diamonds for an astounding 2,500 years.

 

As bewitching as diamonds are they have produced more than their fair share of myths over the centuries. They’ve been attributed with increasing potency,preventing lechery, driving away nightmares, counteracting poison, warding off evil, protection from wild beasts, healing sickness and (naturally) attracting good fortune. There’s also the lie detector myth: that diamonds will darken in the presence of a guilty person and brighten in the company of an innocent one; and the magical reproduction legend: that diamonds sprinkled with morning dew and left in the dark can reproduce offspring! If only!

 

Despite these fanciful ideas some of the amazingly real attributes of diamonds include: their age – the first diamond deposits were brought to the surface of the earth approximately 2.5 billion years ago while the most recent deposits are roughly 50 million years old; their hardness – diamonds are so hard they can only be polished by other diamonds; rarity – more than 250 tons of ore need to be blasted, crushed and processed to yield one carat of rough diamond and of that rough, only 20% is suitable for gem cutting; density – diamond is so dense that it actually slows down light to less than half its normal speed - 80,000 miles per second;

fluorescence – if you’re in a nightclub and someone’s ears or fingers start to glow then diamonds are most likely the culprit, 30-40% of diamonds glow blue when exposed to ultraviolet light and some will even glow green, yellow, white or (extremely rare) red.

While Africa is known as the Diamond continent, it is actually in Australia that the largest reserves are to be found – including the very rare and highly valued pink and red fancy colored diamonds.

Diamonds weren’t cut until the 14th century and it wasn’t until 1725 that deposits were discovered in Brazil and 1866 until South Africa’s substantial storehouse was unearthed.

 

Characteristics

Diamonds are made of pure carbon atoms that exist deep in the ground, exposed to intense heat and pressure over billions of years. Over time, this pressure builds up and forces the diamonds and rocks up toward the surface in a volcanic-like explosion. The explosion creates a very deep, wide hole called a " kimberlite pipe"into which most of the diamonds settle. These “pipes” resemble gigantic carrots encrusted with diamonds. It can take years to fully excavate an entire pipe.

Diamonds also make it to the surface through wind and water erosion, often in coastal areas scattered around the world.

While diamonds exist in a broad color range, they all posses the following features: high refraction, high dispersion or “fire”, very low reactivity to chemicals, and extreme hardness.

If diamonds are so hard, how then (you might well ask), are they cut?

The crystalline formation of a diamond gives it four points of cleavage. A sharp, accurate blow at one of these points will split the diamond. This is (obviously) a very skilled job and while it takes years of training the tools of the trade remain a simple blade and hammer. This is actually a growing industry with Israel and India recently emerging as new centers of skilled diamond cutters.

After cleaving the diamond is shaped. Today this can be done by computerized machinery but more often is still done by hand and typically involves four specialists: The Blocker: who cuts out the rough shape of a diamond; The Top Maker Brilliandeer: who cuts the table and the facets above the girdle; The Bottom Maker Brilliandeer: who cuts the pavilion under the girdle; and the Girdler: who cuts the girdle and the facets around it.

Finally the diamond is polished with fine diamond abrasives creating the stone's many angled planes, or facets. Each facet must be in perfect geometric proportion to every other in order to provide maximum reflection. Only when all these stages have been done is the diamond ready to be set and presented to the buying public.

Diamonds have a high refractive index and dispersion. This is what gives diamonds the brilliance and ‘fire’ we know. In fact most diamonds are not colorless, but are slightly to noticeably yellow. Intense, attractive colors like yellow, pink, blue, green and rarely red are known as “fancy” colors.

 

Evaluation

Diamonds are easier to shop for than other gemstones because they have an accepted grading system that is universal. The most highly valued diamonds are the etremely rare bright red, which have sold for up to $1,000,000 per carat.

A diamond’s value depends on the four "C's": clarity, color, cut and carat weight. Color is graded from D (clear) to Z (yellow), while clarity is rated from IF (internally flawless – very rare), through VVS (very minute flaws), VS (very small flaws), SI (small flaws), to I (significant flaws).

Diamonds should be faceted so that the maximum amount of light is reflected back through the top of the stone. A poorly cut diamond will appear dull and lifeless. The round brilliant is the brightest cut. While oval, pear and marquise cuts appear larger than rounds they are not as brilliant.

 


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Emeralds

Colors: Green

Refractive Index: 1.56 - 1.59

Durability: Slightly fragile to tough

S.G.: 2.67 - 2.84

Material: Beryl

Treatment: Assume oiled

Hardness: 7.5 – 8

Availability: A variety of sizes

Localities: Columbia, Brazil & Zambia

Price: Low to very expensive

Common Shapes: Emerald cuts, ovals & cushions

 

Interesting Facts

 

The mining of emeralds has been dated back to more than 3,000 years ago, during the time of the Ancient Egyptian Empire. The “green fire” was so mesmerizing that the Spanish Conquistadors went on a bloody campaign to find the location of the emerald mines in South America. In 1557, the campaign finally ended with the discovery of the spectacular Muzo and Chivor mines in present day Columbia.

 

Brazil and Zambia produce large quantities of fine emeralds; however, many still consider Colombian emeralds to be of highest quality. Very fine emeralds, though in small quantity, are also produced in Pakistan and Zimbabwe. Emeralds of Zimbabwean origin are sometimes called “Sandawana” emeralds, which refer to the region where the gemstones are mined.

 

 

Characteristics

 

Emeralds contain beryl as the base mineral, while the presence of chromium and vanadium gives this gemstone the “green fire”. Colombian emeralds are known for their vivid green color, while Brazilian emeralds are known for their variety of color, ranging from light green to fine medium dark green.

 

It is quite rare to find emeralds of fine quality over one carat in size, for large emeralds sometimes contain eye-visible inclusions, known as “jardin” or the “garden”.

With the hardness close to 8 on the Moh’s scale, emeralds are quite durable. However, ultrasonic and steam cleaning could damage the stone, causing fractures.

Therefore, professional jewelers should only clean emeralds.

 

Evaluation

 

Clarity and transparency are the most important characteristics when evaluating the value of emeralds. When evaluating from a face up position, very fine quality emeralds should enable the viewer to see the back facet. The brightness of the gemstone, which is determined by the cutting and the number of inclusions, is also an important evaluation factor. Intense medium green emeralds command the highest value. The purity of the green color is crucial to the value and the beauty of the stone, with blue or yellow overtones diminishing its value.

 


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Garnet

Colors: All but Blue

Refractive Index: 1.72 – 1.94

Durability: Slightly fragile

S.G.: 3.40 – 4.30

Material: Various

Treatment: None

Hardness: 6.5 – 7.5

Availability: Varies with type

Localities: Kenya, Sri Lanka, Thailand, Brazil, India & Arizona (USA)

Price: Low to expensive

Common Shapes: Ovals, round, cushion & fancy shapes

Interesting Facts

 

The history of garnet goes back as far as the Bronze Age (more than 5,100 years ago), where this gemstone was very popular amongst craftsmen and artisans. According to Christian and Jewish mythologies, when God’s wrath clouded the earth with thunderous storms and endless rain during the Great Flood, a radiant red garnet guided the way for Noah, ultimately leading his ark to salvation.

Malaia Garnet,Mandarin Garnet,Mozambique Garnet,Rhodolite Garnet, Spessartite Garnet,Tangerine Garnet, Tsavorite Pyrope Garnet, Demantoid Garnet, Mali Garnet, Color Change Garnet.

Unlike other gemstones, garnets are believed to contain both protective and destructive rudiments. The crusaders engraved garnets into their body armors, believing that the protective power of the stones would lead them to safety. On the other hand, some Asian cultures added this gemstone to bullets, believing that garnet’s destructive power would greatly amplify the enormity of a wound.

 

The name “garnet” is believed to have derived from a fruit called “pomegranate”, which contains reddish color seeds, similar to garnet in color.

 

Characteristics

 

Garnets are in actuality a group of related minerals, containing cubic crystalline structure with slight variations in their chemical compositions. In all, there are 7 major

types of garnets, which include Almandine, Pyrope, Spessartine, Grossular, Andradite, Rhodolite and Malaia.

Almandine Also known as “almandite”, almandine garnets are the most common variety. As a result, many have associated its fine red wine color (violet red to brownish red) as

the “garnet color”. The size of almandine garnet varies from small to large. Star almandine garnet can occasionally be found with a rare four-rayed star. Most of the finest almandine garnets today are mined in India and Brazil.

 

Pyrope - Pyrope garnets are another garnet type which are dark red in color. Most of these stones available today are mined in Arizona, and are often called “anthill garnets”,

as they are often found in small pebbles close to anthills.

 

 

Spessartine -Spessartine garnets, also known as spessartite, are the orange to red orange variety, often referred to as “root beer” colored garnets. Its name is derived from

Spessart, Germany, where it was discovered. Today, Brazil, Madagascar and Sri Lanka are the primary locations where this orange variety of garnet is mined.

 

Grossular -Unlike other garnet varieties, grossular garnets appear in many colors, extending from colorless, yellow, orange, green to exceptional pink. The most sought after

color of grossular garnets is the medium dark green variety, known as tsavorite, which is named after Tsavo National Park on the border of Tanzania and Kenya where it was discovered. The color of tsavorite ranges form light green to very dark green. The finest stones are eye clean with an intense medium green color.

 

Andradite –Andradite garnets are undoubtedly one of the most rare gemstones available today. The intense medium green variety, known as demantoid, is quite spectacular to observe. Having the highest refractive index of all garnets, dematoid’s brilliance is second to none.

 

The finest stones will contain some inclusions, called “horse tail” inclusions, which are fibrous strands of byssolite.

 

Small amounts of demantoid garnets were mined in Russia during the 19th century. However, most of the stones today are found in antique jewelries, as the mine has been long depleted.

 

Other color varieties of andradite garnets do exist, however their beauty is incomparable to the stunning brilliance of demantoids.

 

 

Rhodolite - Many have considered rhodolite to be the “queen of garnets”. This is due to its delicate pink to violet red color, which is similar to that of the rhododendron flower (a

common symbol of feminine beauty). Chemically, this garnet’s composition is a blend of almandine and pyrope.

Rhodolites of most spectacular pink are mined in Sri Lanka, Tanzania and Zimbabwe.

Malaia - Malaia garnets, mined only in Tanzania, have been considered the “outcast” for many years (malaia means “outcast” in Swahili). It was not until 1970’s that its beauty

was truly appreciated by the gemstone world. Malaia garnets are available in numerous shades of orange, ranging from soft peach to intense reddish orange.

Similar to rhodolite, malaia garnets’ chemical composition is a mixture between many general types of garnet, including grossular, spessartine, almandine and pyrope.

 

 

Evaluation

 

When evaluating the value of garnets, color is the most important characteristic. The color must be intense and uniform with a tone that is not too light or too dark. Fine garnets should be eye clean with minimal inclusions under magnification. Size is also a very critical determinant of the stone’s value. For fine garnets of a rare color, the value of the gemstone will increase tremendously as the size increases.

 

 

 

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Jade

Colors: White, green, yellow, red, orange, lavender, black & brown

Refractive Index: l.66 - l.68

Durability: Tough

S.G.: 3.30 – 3.38

Material: Sodium aluminum silicate

Treatment: Dyeing

Hardness: 6.5 – 7

Availability: Some colors meet demand; others are very rare

Localities: Myanmar (Burma)

Price: Low to very expensive

Common Shapes: Cabochons in oval, round, navette, etc. Some carved

 

Interesting Facts

 

The "stone of the loins" is how the Spanish refer to jade – "piedras de ijada" – and this is where the English word derives from. The term jade actually refers to two distinct types of stone that closely resemble one another – the more common nephrite and the more expensive jadeite.

 

Long associated with the Chinese culture, jade was actually used by the Central American Mayan civilization hundreds of years before it attained a royal position in the Middle Kingdom. The Mayans mined jadeite in Guatemala making it into weapons and tools.

 

The Chinese cult of jade worship began in the Neolithic era when nephrite from the Kunlun Mountains was used in religious ceremonies, agriculture and war. The “Stone of Heaven” became so influential with the Chinese emperors that Confucius even wrote that men should aspire to its qualities of benevolence, intelligence, righteousness, humility, resonance, loyalty, faith, virtue and truth.

 

Jade is tougher than granite and more difficult to carve than solid steel. When diamonds were first introduced to China sometime between 1005 and 221 BC, they were originally more highly valued as jade carving tools than as gems.

 

Although jade has long been associated with the Chinese culture it wasn’t until l784 that Burmese jadeite found its way there and superseded the local nephrite as the imperial stone.

 

The New Zealand Maoris also used nephrite weapons. The fibrous structure of nephrite is very densely packed making it the "super skull crusher" gemstone. In spite of its low hardness, it is considered to be the toughest gem material.

 

Jade is believed to bring good luck, health and fortune, assist during childbirth and protect infants from disease. Throughout Asia millions wear jade amulets believing that they give the owner power, knowledge, pure thoughts, long life and immortality.

 

 

Characteristics

There are two distinct types of jade – jadeite and nephrite. Nephrite is found in scattered areas around the globe and appears in a wide variety of colors. Jadeite predominantly comes from Burma and while it is available in gray, yellow, pink, blue, lavender, red, white, brown and black, it is most popular in the classic green that most people associate with the stone.

 

Evaluation

Intensity of color and transparency are the most important factors in judging quality. While jade is never fully transparent, the closer it gets to transparency, the higher it is valued. The most highly valued colors are the very rare “Imperial” green and apple green. Lavender jade is also very rare and attains high prices. A green swirl of jade in an otherwise white stone is known in Chinese as “moss in snow” and fetches princely sums.

 

Jadeite must be examined with a microscope to see if it has any value-reducing internal fractures. Quality of carving is also an important value factor.

 

Frequently jadeite is dyed green or lavender. Most dyed jadeite does not look quite right. Jade is often sold by the piece rather than by carat weight.