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Perious Stone Black Pearl

Monday, August 17, 2009
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For centuries, Tahiti & Her Islands have evoked an image of paradise. And within her turquoise lagoons grow one of nature's most magnificent creations - the Tahitian Black Pearl. As Tahitians, we take great pride in the black pearl and over the years Moorea Black Pearl has developed a reputation of quality and service with an international clientele that spans the globe. What separates us from many of our competitors is that in addition to selling both wholesale and retail, we also happen to be producers. Having our own pearl farms allows us to sell directly to you. By avoiding the middle-man, you are able to reap great savings. We have two stores on the island of Moorea and it is our pleasure to share with you our knowledge and love of the beautiful Tahitian black pearl. Through our website, we invite you to learn more about this precious gem. We feel strongly that the more you know about black pearls, the more you will appreciate Moorea Black Pearl. Welcome to Moorea Black Pearl where you will always find extraordinary pearls at exceptional prices.

Semi Perious Stone Lapiz Lazuli

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Lapis Lazuli is one of the first gemstones mentioned in the Bible, and is believed to protect its wearer from evil. Lapis contains the energies of royalty, wisdom, patience, truth, mental attainment, improved communication, contentment, artistic inspiration, personal integrity, loyalty, and illumination. Lapis is believed to attract good fortune, heighten concentration, clarity, and strengthen instincts. Lapis is said to promote success in love, encourage cheerfulness and self-confidence by providing a sense of wellbeing. Lapis advocates creative expression; helps in judicial matters; assists during time of mourning; releases tension, anxiety; and aids sleep. Lapis activates the thyroid gland; benefits blood circulation, childbirth, digestion, and feminine discomfort. Popular with ancient alchemists, Lapis was used in medicine, cosmetics, and paintings. Lapis is also believed to confer ability, success, divine favor, (ancient) wisdom, and cure sore throats. Lapis gives relief from pain, both physical and psychological, as well as combats cruelty and brutality. Lapis heals the martyr syndrome and aids discrimination of wisdom.The quality of gemstone will be superb and Rates are for per carat.Suppose you want to buy an five carat stone, then plz add 5 in quantity coloumn to avoid any confusions.

Semi Perious Stone GARNET

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Garnet ignites and refuels passion and romance as well as gives a sense of self-confidence. It also clears a path for new beginnings. Garnet helps to destroy the negative feelings that keep us trapped by fear and guilt. It is considered a gem that enhances vitality, sexuality, and commitment, love, and purity. Often used as an anti-inflammatory and blood-clotting agent, Garnet is thought to be a healer and protector from toxins. It is used as a remedy against food poisoning and assists in treating infections of the lungs and kidneys; sleeping, pulmonary, and heart disorders; and helps to strengthen bones and the spine. It has been claimed to work on a cellular level, giving relief to joint discomfort, sore muscles, frostbite, arthritis, fever, and gallstones. Garnet was even used to treat Yellow Fever and jaundice many years ago. It is said to bring good health, and riches if a dragon is engraved out of Garnet and worn as a talisman, according to ancient Greco-Roman tradition. Garnet can be worn as substitute for RUBY.The quality of gemstone will be superb and Rates are for per carat.Suppose you want to buy an five carat stone, then plz add 5 in quantity coloumn to avoid any confusions.

Semi Perious Stone Malachite

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Malachite is also known as Kidney stone.It is thought to be a protective stone, especially for children, warning the wearer of impending disaster by breaking into pieces prior to the event. Malachite was worn as protection from black magic and sorcery during the middle ages, and it was believed to keep evil spirits away and help babies sleep soundly if Malachite was affixed to an infants cradle. Malachite is said to provide protection against radiation; is used to relieve arthritis and rheumatism symptoms; mend broken bones and torn muscles; and give relief from asthma and swollen joints. Believed to cleanse the body on a cellular level, Malachite improves the immune system and stabilizes the wearer's energy level. Malachite assists in the relief of physical pain, tumors, birthing, menstruation, toothaches, and childbirth. Malachite is also believed to provide insight into causes of disorders/diseases of the mind. For prosperity, Malachite can be placed in a cash register, or in the four corners of a business to draw customers. Malachite is also believed to teach patience and knowledge; encourage leadership, emotional maturity, loyalty, wisdom, and self-understanding.The quality of gemstone will be superb and Rates are for per carat.Suppose you want to buy an five carat stone, then plz add 5 in quantity coloumn to avoid any confusions.

Semi Perious Stone CITRINE

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Citrine is thought to dispel fear, stimulate mental focus and endurance, and eliminate self-destructive tendencies. A stone that symbolizes success in all walks of life, it is also useful in building happiness, goodness, truth, comfort, stability, generosity, creativity, prosperity, strength, confidence, protection, and pleasure. Physically, Citrine is said to aid in digestive, circulatory, cardiovascular, kidney, liver and muscular disorders. It’s also claimed to be used as a treatment for appendicitis, gangrene, digestive tract problems and red and white corpuscles.Citrine can be worn as an substitute for YELLOW SAPPHIRE.The quality of gemstone will be superb and Rates are for per carat.Suppose you want to buy an five carat stone, then plz add 5 in quantity coloumn to avoid any confusions.

Semi Perious Stone AQUA MARINE

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Aquamarine enhances creative self-expression and helps those burdened with great responsibility by giving strength and wisdom and clarity of mind. Attuned to the ocean, it provides soothing calm, alleviating phobias and fears. This stone helps those who are judgmental become more tolerant of others, inspiring peace and tranquility. Aquamarine rekindles love in married couples and signifies making new friends. Legend says it's a treasure of mermaids, and it's power keeps sailors safe at sea. Aquamarine has been useful in reducing fluid retention, treatment of eyesight problems, coughs, thymus gland, the liver, swollen glands, the neck, ears, jaw, toothaches, and stomach difficulties.It is an ideal gem for those born on 3rd, 12th, 21st or 30th of a month (birth number 3) or for Pisces or for those in whose cases Jupiter is well placed in the ascendant intheir natal charts. It is also a recommended stone for Leo.The quality of gemstone will be superb and Rates are for per carat.Suppose you want to buy an five carat stone, then plz add 5 in quantity coloumn to avoid any confusions.

Semi Perious Stone Amethyst

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Amethyst apart from being the beautiful charming purple gemstone is also known to be powerful and effective in bringing about a change in the person, internally and externally. Some people believe that the amethyst gemstone can be used to remove negativity and fear of failure and bring about a more intense spirituality and positive energy leading to success.It is good for natives born in the month of Jan or Feb of any year and for pisces( those born between Feb 21 and March 20), particularly those who may wish to obtain professional gains. They would acquire magnetic personality and would be able to win over the opposite sex with ease, with the use of this gem. The quality of gemstone will be superb and Rates are for per carat.Suppose you want to buy an five carat stone, then plz add 5 in quantity coloumn to avoid any confusions.

Blue Sapphire Details

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Blue Sapphire:
CHEMISTRY Al2O3
CRYSTALLOGRAPHY Hexagonal
REFRACTIVE INDEX 1.757 - 1.779
HARDNESS 9 SPECIFIC GRAVITY 3.99 - 4.0
CLEAVAGE None
HEAT SENSITIVE No

WEARABILITY* Excellent
SPECIAL CARE INSTRUCTIONS None

ENHANCEMENTS Heat treated. Common. Diffusion treatment, (places a thin blue coating on colorless sapphire.) Occasional. Irridation, (turns colorless gems yellow, orange or light blue.) Rare.

Hessonite Details

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Hessonite:
Hessonite is one of the gem varieties of the garnetmineral, grossular. The other gem variety of grossular is green and is called Tsavorite. Hessonite is usually cinnamon brown and has been called "cinnamon stone". Hessonite can also be orange; this color is becoming common on the gem markets. Gem quality hessonite is found at Sri Lanka, Brazil and California.

Facts about Hessonite:

VARIETY INFORMATION:
VARIETY OF: Grossular Garnet, Ca3 Al2 Si3 O12.
USES: Gemstone.
COLOR: various shades of brown and orange.
INDEX OF REFRACTION: 1.73 - 1.75
HARDNESS: 6.5 - 7
CLEAVAGE: none
CRYSTAL SYSTEM: isometric

Cat's Eye Details

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Cat's Eye:
Chrysoberyl is a hard, tough, and durable gem. Although it lacks fire, specimens are very valuable. Most chrysoberyl gems are yellow, and some are brown or green. A rare, costly variety, known as alexandrite, exhibits different colors in natural and artificial light. If viewed in sunlight, its color is dark yellow-green to greenish-blue. If viewed in artificial light, its color is strawberry-red. Alexandrite was discovered on the birthday of the Russian Czar Alexander II, and was named in his honor.

Another expensive form of chrysoberyl is the unusual cat's eye variety. When polished as cabochons, these stones exhibit a narrow band of concentrated light along the width of the gem. This effect, known as cat's eye effect, is caused by inclusions of fine, slender parallel fibers in the gem. The cat's eye variety may be called "cat's eye", cat's eye, "precious cat's eye", "oriental cat's eye", "catseye", or "chrysoberyl cat's eye". Many other gems also exhibit a cat's eye effect, but only chrysoberyl's cat's eye enjoys the privilege of having the name "cat's eye". (All other gems that exhibit a cat's eye effect must have the gem name preceding, such as "quartz cat's eye", whereas chrysoberyl's cat's eye is known simply as "cat's eye".)

Facts about Cat's Eye
Mineral information: Chrysoberyl

Chemical composition: BeAl2O4

Color:Yellow, orange-yellow, yellow-green, green, bluish-green, and brown. The variety alexandrite becomes reddish in artificial light.
Hardness: 8½
SG: 3.5 - 3.8
RI: 1.744 - 1.755
DR: .009
Luster:Vitreous

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Diamond Details

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Diamond:
Diamonds are our most popular gem. They have great brilliance, plus the delightful quality know as fire, or dispersion. (That is the ability to take in white light and throw back flashes of color.)...Diamonds are graded into dozens of categories. While this is helpful to the professional, it can be confusing to the average consumer. I especially feel for the young couple looking for their first diamond engagement set. They want to gather enough information to make an intelligent decision, but can be overwhelmed by all the data thrown at them....To help you I have done two things. First, there is a description of how diamonds are graded. Once you understand that, I make recommendations on chosing a diamond. Please read on.

DIAMOND GRADING:
Diamonds are graded on four qualities, commonly known as the 4 C’s:
COLOR, CLARITY, CUT, CARAT...

COLOR:
The closer a diamond is to being colorless, the greater it’s value. When the current grading system was introduced in the 1930’s, diamonds were commonly called grade A, B, or C. So the current system began color grading with the letter D, to avoid any confusion.... Colors D, E and F are the highest grades. They are described as “near colorless.”... Colors G, H, I and J come next. They are described as “white.”... The colors from K to Z are tinted, (usually yellow or yellowish brown.) Those that are just lightly tinted, K, L and M are often said to “set white.” That means that they are so lightly tinted that they will appear white if set in yellow gold. You would however notice their color if set in white gold or platinum. ... As one gets further down the alphabet, the tinting gets stronger and the value lower. That is, until you get to the extreme. As the color becomes richer, you have a fancy colored diamond, rather than an off colored one. Then the value starts going up again.... Color grading is done by placing a diamond next to a set of previously graded gems. The color is compared to the graded gems to see which it comes closest to matching.... While this low tech approach is accurate, it is also expensive and time consuming. A compromise is often made on smaller gems, by grading batches within a range, rather than coming up with a specific grade. You will usually find diamonds under a carat graded as GH, or IJ, meaning that they are in that range.... This information is meaningful and saves you quite a bit of money. It costs over $100 to accurately grade a diamond. If you have a large diamond, where subtle differences in quality grades make a significant difference in price, then it is worth while. However, that isn’t cost effective for the majority of gems.

CLARITY:
The clarity of a diamond is determined by the size and number of inclusions inside of it. An inclusion can be another mineral, a fracture or occasionally a void. Simply put, it is anything that will interfere with the free passage of light.... Just like with color, there are many clarity grades. They are judged by what an expert can see at 10 power magnification, under ideal conditions. The highest grade a diamond can get is Flawless. That means no inclusions can be seen at 10 power magnification. It does not mean inclusions can’t be found with higher magnification, nor should you assume it is the only grade with no inclusions visible to the naked eye.... Clarity grades use the letters V, S and I. They stand for Very, Small, and Inclusion. Progressing from Flawless, the grades are VVSI1, (Very, Very Small Inclusions One,) VVSI2, VSI1, VSI2, SI1 then SI2. These are the grades of diamonds that have no “eye visible” inclusions, those that can’t be seen with the naked eye. (Note, some SI2 stones will have small, eye visible inclusions.)... As we progress down the grading scale, there is I1 and I2. These have eye visible inclusions, but are still considered to be gem grade.... Then there is P1 and P2. They are not usually considered gem grade because so little light will pass through them. However, since they have the magic name diamond, they do show up on the market regularly. ... Beware of ads “1 carat diamond ring, $299.” Just because something is a diamond, doesn’t mean it is a gem. In fact, the vast majority of diamonds mined are usually considered “industrial grade” and are used as abrasives. Many of these "industrial grade diamonds," those graded as P1 and P2, find their way into jewelry simply because they had the advertising appeal of being diamonds.

CUT:
This one of the hardest properties to judge, plus there are a number of factors to consider. The first one has to do with the brilliance of the gem.... The pavilion facets of the gem are intended to act as mirrors, to reflect the light entering the stone, back towards the observer. However, the angle they are cut at has a lot to do with how efficiently they work. Note: If you are unfamiliar with this terminology, see our article on “Gem Cutting Terms.")... The ideal angle for diamond pavilion facets is 41 degrees. This is usually quite convenient, based on the shape of a standard diamond crystal. Unfortunately, not all mined diamonds are in excellent proportions. The diamond cutter is often faced with having to compromise between maximum brilliance and maximum yield. The economics are such that, if the cutter removes too much material from the original crystal, there is no profit in it. Hence, many diamonds get cut at less than ideal proportions.... Diamonds have a high refractive index, which gives them their great brilliance. A little cheating here or there is insignificant. However, if the cutter varies a little further from the ideal the brilliance begins to suffer. Still more and you get a gem that just doesn’t stand up to others in terms of brilliance or fire.... There are no standards for this. Most jewelers are familiar with correct proportions and can judge it from the shape. The best test for most of us is to simply compare the gems side by side. If you have two diamonds of the same grade and one is significantly brighter than the other, the cut is the difference.... Please understand that the above discussion assumes we are talking about round diamonds. Because of their symmetrical proportions, all the major facets can be cut at the same angle. The same does not hold true for other shapes. ... Many people prefer a marquis shape. This is fine, but do not expect a marquis, or any other shape, to be as brilliant as a round. On a marquis it is necessary to cut a number of facets to accommodate the shape. The angles these facets get cut at vary, slightly to greatly, from those that give the greatest brilliance. This is a simple fact of physics: the more facets that are cut at the ideal angle, the greater the brilliance of the gem. ... When looking for diamonds you may come across the terms, "Single Cut,” “Old Mine Cut” or “European Cut.” These are gems that only have eight facets running from the girdle down and eight up to the table. That makes a total of 17 facets. A standard round brilliant cut has 57 facets. ...These “single cuts” are usually used on small accent stones, but occasionally you will find an older diamond of decent size with this cutting. Obviously, these gems won’t have the brilliance of a full cut diamond, therefore they aren’t worth as much.... Another factor that comes under the heading of cut have to do with the shape of the gem. An ideal cut gem should be symmetrical, not lop sided. This point should be obvious, but sometimes it is helpful to point it out. A misproportioned gem can be camouflaged in it’s setting and you might not notice it until you have paid for it. This may not bother you, but it might lead to dissapointment.... Though hard, diamonds are also somewhat brittle. (If this doesn’t make sense to you, see the article on Hardness and Wearability. The girdle of the gem is the widest part when viewed from the top and the thinnest when viewed from the side. If cut too thin, it can present a weak area that is just asking for trouble. These illustrations will give you an idea of what normal proportions are. Some girdles get cut to a knife edge and this is definitely something to be avoided.

CARAT:
This is by far the easiest of the factors to understand. Simply put, smaller diamonds are more common than large ones. Therefore smaller diamonds cost less per carat than large ones.... If you were to see a diamond broker's price list, under each grade, the price per carat would go up with size. A grade of diamond that would cost $900 per carat in the ½ carat size might cost $1100 per carat at ¾ of a carat and $4000 in a full carat.

CHOOSING A DIAMOND:
You should spend six months income on an engagement ring. I know that, I heard it on television! For a salesman that is a great idea. However, picking a diamond is something much more personal than finances.... Economics vary from person to person and family to family. I wouldn’t presume to advise you on how much you can afford, but I can help you wade through the morass of grading information and put it in common language.... As a rule, I suggest diamonds that are in the white range of color, (G, H, I or J,) and those with clarity grades SI1 or SI2. Visually these are wonderful diamonds. They are bright and lively they will dazzle all your friends!... You might consider a lower grade of color if the right deal was presented to you. An L graded diamond can look white in a yellow gold setting and be quite brilliant. The fact that it costs less per size might be worth your while. I wouldn’t recommend looking for this grade, but if you found one in a setting that you really love it would be worth serious consideration.... Going down in clarity grading can occasionally be worth your while too, depending on the individual diamond and setting. Sometimes the “eye visible” inclusion that got it that ranking is insignificant and the overall appearance is still delightful.... Going down further in quality is rarely worth while. I know a lot of jewelers make their living by supposedly underselling the competition, when in fact they are selling lower grade gems. Without better quality diamonds near by to compare with, the customer is often convinced they are getting a great deal. The diamonds sparkle, the price and terms are just, oh, so sweet!... The disappointment comes later. Imagine your fiancĂ© showing off her engagement ring, (something they usually get great joy out of,) only to find hers is dull compared to those of her friends. You no longer have a great deal. The enjoyment of the diamond goes way down when you compare a lower quality gem to a good one.... Please consider this factor carefully! While choosing a diamond is a personal thing and not everyone will have the same opinion, most folks will get more enjoyment from a higher quality dazzler, than a larger but mediocre gem.... How about going up in quality? That is a personal matter. If you get an emotional boost from owning the biggest and the best and can afford it, then you certainly should. However, for most people who simply want a fine gem on their finger, it isn't necessary.... People who are serious about their diamonds and get to look at a lot of them, get a real joy out of finding those rare gems that are nearly colorless or nearly clean under magnification. These gems are much rarer and therefore demand a higher price. But that does not mean they are much prettier, nor does it mean that you will get more enjoyment out of them.... If you were to set two well cut diamonds side by side, one graded D, VVSI1 and the other G, SI1, you would see very little, if any, difference with the naked eye. You would have a strong emotional reaction when you heard the prices though!... The point is simple, these are the rarest quality gems and the difference is only apparent to the sophisticated diamond appraiser who inspects them carefully with magnification. ... There is occasionally a difference between a diamond graded SI1 and SI2. (SI1 is defined as “small inclusions, somewhat easy to find.” SI2 is defined as “small inclusions easy to find.”) When I look at a gem graded SI1 I usually see something like the first illustration. One or two tiny dark spots that have no effect on the brilliance of the gem. ... Those graded SI2 have inclusions placed near the center where they are more visible, or many more of them. Some gems graded SI2, like the first illustration, will have no significant difference in brilliance. In an extreme case, where there are many inclusions, (even though none are large enough to be seen without magnification,) they may make up 5% or more of the visible area. That means a 5% or more reduction in brilliance. ... One of the most important elements of a diamond's appearance is the cut. This is a difficult element to judge. Diamonds are rarely cut to ideal proportions, but they have such high optical properties that most of them are still beautiful. Without getting overly technical, you can judge the quality of cutting by simply comparing diamonds side by side. Look for overall brilliance and fire; those little flashes of color. If the diamond you are considering does not have the sparkle of the other gems, then keep looking.... To summarize, it is usually best to go with quality rather than size, but if your budget is limited the rarest qualities may not be worth your money.

Facts about Diamonds:
CHEMISTRY C
CRYSTALLOGRAPHY Isometric
REFRACTIVE INDEX 2.417
HARDNESS 10
SPECIFIC GRAVITY 3.515
CLEAVAGE Perfect 4 directions
HEAT SENSITIVE No
WEARABILITY* Excellent
SPECIAL CARE INSTRUCTIONS None
ENHANCEMENTS Some colors produced by irridation, common. Laser drilled to remove inclusions, common. Cracks filled with glass, occassional.

Yellow Sapphire Details

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Yellow Sapphire:
In the gem trade, sapphire refers to the blue variety of corundum. However, excluding red ruby, it scientifically encompasses all other gem varieties of corundum. (In essence, ruby is really a red sapphire, since ruby and sapphire are identical in all properties except color.) Sapphire is the most precious of blue gemstones. It is a most desirable gem due to its color, hardness, durability, and luster. The most valuable color of sapphire is cornflower blue, known as Kashmir sapphire or Cornflower blue sapphire.

Until the last century, all sapphires (excluding blue) were called the same name as a popular gemstone of that color with the prefix "oriental" added to it. For example, green sapphire was known as "oriental emerald". The practice of applying the name of a different gemstone to identify the sapphire was misleading, so these names were virtually abolished. What was once called "oriental emerald" is now called "green sapphire". The same holds true for all other color varieties of sapphire. However, the word "sapphire" in its plain context refers only to blue sapphire, unless a prefix color is specified. Sapphire with a color other than blue is often called a "fancy" in the gem trade.

Inclusions of tiny, slender, parallel Rutile needles cause polished sapphire gems to exhibit asterism. Sapphire gems displaying asterism are known as "star sapphires", and if transparent are especially prized. Star sapphires are usually in six ray stars, but twelve ray stars are also known. Very rarely, sapphire also exhibits cat's eye effect.Color zoning, which forms from growth layers that build up during the formation of the stone, is present in certain sapphires. However, uniformity of color is an important factor in a sapphire's value.

Colorless and pale blue sapphires from certain localities may be heat-treated to give them an intense blue color. Heat-treatment may also improve the clarity of some sapphires by removing tiny inner inclusions. Sapphire is pleochroic, displaying a lighter and more intense color when viewed at different angles. Some pleochroic sapphire is blue when viewed at one angle, and purple at a different angle.

A rare variety of sapphire, known as color changing sapphire, exhibits different colors in different light. In natural light, color changing sapphire is blue, but in artificial light, it is violet. This effect is the same phenomenon seen in alexandrite.

Sapphire was first synthesized in 1902. The process of creating synthetic sapphire is known as the vernueil process. Only experts can distinguish between natural and synthetic sapphire.

Sapphire is a tough and durable gem, but it is still subject to chipping and fracture if handled roughly.

VARIETIES:
Kashmir Sapphire - Sapphire with a distinct velvety-blue color
Cornflower Sapphire - Synonym of Kashmir sapphire (above)
Cornflower Blue Sapphire - Synonym of Kashmir sapphire (above)
Star Sapphire - Sapphire displaying asterism
Padparadschah - Orange-pink variety of sapphire

Color Changing Sapphire - Sapphire exhibiting a different color in natural and artificial light
Bi-colored Sapphire - Sapphire with more than one color
Cat's Eye Sapphire - Sapphire exhibiting cat's eye effect
Fancy Sapphire - Any sapphire with a color other than blue
Verneuil Sapphire - Synthetic, laboratory-grown sapphire.

Nowadays, sapphire is classified by its color in the gem trade (i.e. green color sapphire is "Green Sapphire"). Colorless sapphire is usually called "White Sapphire".

The "oriental" prefixes are not used anymore, but they are still occasionally seen. Below is a list of all the "oriental" sapphires:
Oriental Topaz - Straw yellow, gem quality sapphire
Oriental Emerald - Light to dark green, gem quality sapphire
Oriental Amethyst - Violet to pink, gem quality sapphire
Oriental Peridot - Yellow-green, gem quality sapphire
Oriental White Sapphire - Colorless, gem quality sapphire

Some other (rarely used) variety names:
Australian Sapphire - Dark blue to nearly black sapphire
Bengal Amethyst - Purple sapphire
Blue Alexandrite - Synonym of color changing sapphire
Burma Sapphire - Synthetic, laboratory-grown blue sapphire
Burmese Sapphire - Synonym of Burma sapphire (above)
Ceylon Sapphire - Light blue sapphire
Indian Topaz - Yellow to yellow-brown sapphire
King Topaz - Yellow to yellow-brown sapphire
Rose Kunzite - Synthetic pink sapphire
Star Topaz - Yellow star sapphire
Ultralite - Blue sapphire
Facts about Yellow Sapphire:
Color: Blue, yellow, green, white, colorless, pink, orange, brown, and purple
Hardness: 9
SG: 3.9 - 4.1
RI: 1.76 - 1.77
DR: .0008
Luster: Vitreous to adamantine
Mineral class: Corundum
Composition: Be3Al2SiO6

Emerald Details

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Emerald:
Since the time of Cleopatra, emeralds have epitomized the of color in green gemstones. It would be easy to question this statement if all one had seen of emeralds were the commercial, (and poorer,) quality stones which abound on home shopping networks and in some jewelry stores. A fine emerald, though, is a truly breathtaking sight and is well deserving of its placement in the traditional "big four" along with sapphire, ruby and diamond. Emerald is the birthstone for May and for commemorating the 20th and 35th wedding anniversaries.... The center of world emerald mining is in South America with Colombia and Brazil as major producers. The African mines that supplied Cleopatra's passion have long since been played out. However, today the African continent is second only to South America in production, with mines in Zambia, Zimbabwe, Madagascar and Nigeria. ... Each of these world locales typically produces a certain color, size and clarity -- so much so that the term "Colombian" emerald has often been enthusiastically used to describe vivid, slightly bluish green stones of medium to medium dark color, no matter what their actual geographic origin. Likewise, emeralds of lighter color are sometimes called "Brazilian", even if they were mined in Africa. The USA and Japan together purchase more than 75% of the world's cut emeralds.... Emerald, by definition, is a medium or darker green to blue green beryl, in which the green color is derived from impurities of Chromium, Vanadium, or a combination of both. Before 1963 the definition was limited to Chromium containing stones, but the discovery of a large deposit of Vanadium colored stones in Brazil led to modification. ... Varying amounts of iron will affect the color as well, with more atoms of this impurity increasing the bluish tones. In a situation similar to that which exists with the boundary between pink sapphire and ruby; there are chromium colored stones of light to medium light green color which are sometimes sold as emerald, but which are more correctly considered green beryl. Geological conditions were right, it seems, in Colombia to produce exactly the slightly bluish green shade and strong saturation that make stones from that locale the epitome of the variety. ... Emeralds are considered a "Type III" gemstone by GIA which means that they are virtually always included to one degree or another. Because of this designation, a clarity grade of "very slightly included" for example, refers to the normal range for emeralds, not for all gemstones. Well over 90% of the emeralds in commerce have been treated to minimize the appearance of the inclusions. ... The industry practice for treatment, (and that which is considered "standard" by AGTA,) is "oiling". This term refers to the practice of immersing emeralds in a colorless oil or resin. Often this is done using a vacuum chamber to assist penetration. Non-standard treatments go beyond this to using green colored oils and hardened, epoxy-like resins. ... These treatments dramatically improve the appearance of the gems, but necessitate special care in cleaning and setting. Steam cleaners, solvents and ultrasonics can remove the oils, making inclusions which had barely been visible stand out in sharp relief. Luckily, it is possible to have emeralds re-oiled. ... The inevitable inclusions are more than a aesthetic consideration, as they can reduce the structural integrity of the gem as well. Beryls, in general, are good jewelry stones, with a hardness of up to 8 and no troublesome cleavages. Because of the inclusions, emeralds are generally more fragile than other beryls and must be treated more gently. ... Emerald imitations often encountered in the marketplace include: glass, YAG, synthetic spinel triplets, green cubic zirconia, and beryl triplets. Within the last fifty years two major processes have been developed to produce "lab created" emeralds, or synthetics. If you've seen and priced man-made emeralds you might have wondered why they are so costly compared to CZs or some types of synthetic sapphires. Both the flux and the hydrothermal methods of production require costly equipment and are energy intensive. They take a long to time produce and have a low yield of cuttable gems. ... Some of the first lab created emeralds on the market weren't convincing because they were so clean, but the sophistication of today's consumer has led to a trend toward more naturally included looking synthetics. Although this improves their acceptability, it does make it a little more difficult for gemologists and appraisers to prove natural origin. Fortunately, there are signs, particularly regarding the types of inclusions in a gem, which can conclusively verify natural versus synthetic origin.

VALUE CONSIDERATIONS:
Like many stones, the per carat price of fine quality emerald escalates rapidly with size. For example, a recent price guide lists a fine quality, 3 carat Colombian stone as six times more valuable than three equivalent quality 1 carat stones. ... Value factors hinge largely on color with nuances of saturation and hue affecting price to a significant degree. The most desirable color is a slightly bluish green in a medium dark tone with strong to vivid saturation. Clarity is important, but inclusions are tolerated more in this variety than virtually any other gem. Top quality, unenhanced stones, (with certification,) can bring as much as 50% more in price than treated stones of the same size, color and clarity.

Facts about Emeralds:
CHEMISTRY Be3Al2Si6)O18 + Cr
CRYSTALLOGRAPHY Hexagonal
REFRACTIVE INDEX ~ 1.57 - 1.59, varies with source.
HARDNESS 7.5 - 8
SPECIFIC GRAVITY 2.68 - 2.78
CLEAVAGE Indistinct
HEAT SENSITIVE No

WEARABILITY* Poor to Good, depending on the integrity of the gem.

SPECIAL CARE INSTRUCTIONS Emeralds usually have internal fracutres, so clean with warm or room temperature soap and water. Avoid wearing gem where it will get rough treatment.

ENHANCEMENTS Oiling, common. (Oils and epoxies are used to fill fractures, which reduces their visibility.

Coral Details

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The Story of the Coral:
It is pulled from the ocean depths and hits the surface looking like a mutant from a monster movie. Gnarled, covered with organic parasites and debris, it is not even remotely beautiful. But cleaned, cut, carved and polished, coral becomes an object d'art of rare and costly beauty, as prized today as it was 10,000 years ago.
Coral is discovered in still, clear water between 25 and 1000 feet deep. The intensity and quality of coral color increases with depth, but coral is very sensitive and can breed only in water temperatures between 13 and 16 degrees Celsius. These ideal conditions are met in only several places: The best coral is found in the waters of southern Ireland, the Bay of Biscay to Madeira, in the Canaries and the Cape de Verde Islands, in the Mediterranean, the Red Sea, Mauritius, the Malay Archipelago, and in Japanese waters. Italy is considered the center of coral jewelry creation, and Torre del Greco, near Naples, is where the best coral jewelry in Italy is made. Larger pieces are often fashioned into stunning umbrella handles or walking sticks, while smaller pieces are made into round or egg-shaped beads that are used in necklaces, rosaries and bracelets. Coral is also the classic material for carved cameos but also makes beautiful earrings, brooches, pendants, rings, cuff links, tie bars, belt buckles, inlaid jewelry boxes and pillboxes. A great deal of coral is exported to India and China, where it is used in religious rituals.In America, the native Navajo and the Zuni silversmiths have been the heaviest users of coral jewelry. The Zunis combined it with black jet, though it also contrasts magnificently with turquoise. The San Domingo Indians also worked coral into wampum-style beads.

The Colours Of Coral:

Coral, or Corallo, as the Italians call it, comes in many variations. These are considered the best for fine jewelry.

Red Coral: Classic and expensive, this is the most valued coral of all, favored worldwide for its hardness, beauty, and sanguine hue. Red Coral is brought up from the sandy bottom of the Mediterranean, and the Gulf of Naples near Genoa. It is also found off Algiers and Tunis on the African side, in the waters of Sardinia, Corsica, Catalonia and Provence, as well as along parts of the French and the Spanish seaboard.

Precious, or Noble Coral: A type of red coral called Corallium Rubrum, or Corallium Nobile, Precious coral can be found in the Mediterranean, Sardinia and Sicily, as well as in Tunis, Algeria and Morocco.

Black Coral: This coral is a horny substance particularly good for carving and molding – it actually bends when it is warmed! The black hue is believed to be coral in the first stage of decay, since the color only persists a little below the surface. Once abundant in the Persian Gulf, a similar type is found in the Mediterranean.

Blue Coral: As with Black Coral, this variety is thought to be coral in the first stage of decomposition, since the color usually extends only just below the surface. It is known both as Allopora Subviolacea and Akori. This unusual variety has been found off of Cameroon.

Golden coral: Divers off Maui, in Hawaii, have brought up this pretty variety of coral, which has a resinous or lacquered texture.

Coral From Start To Finish:

Before coral can be “fished”, or harvested, it must grow. First, a gelatinous marine animal deposits calcium carbonate around its body, creating a polyp made of fibrous calcite crystals. These polyps radiate out at 90 degrees, creating branch-like shapes that are built up in the form of hollow tubes fitted on into the other, making a sort of axial skeleton reminiscent of the internal skeleton of any living being. But they are even more reminiscent of scaffolding, upon which the boneless coral polyps proliferate, grow, and thrive as a colony, creating what we see as coral. When fully grown, coral resembles an irregular, dwarf tree covered with barnacles, lime, and salt. 10 inches high -- with an 8 inch spread -- is considered a large find. "Fishing" for coral is really a misnomer: Italians, the leading harvesters in the industry, actually dredge the sea bottom using a specially designed net called an ingegno, a web of ropes attached to a weighted wood cross or beam that is dragged along the ocean floor by a fairly large sailing vessel. This tears up the coral and brings it to the surface. Large boats of 12 to 14 tons require a crew of 10 to 12 men. Most coral "fishing" is done in summer, in order to avoid the dangers of winter storms on the waters. Once the harvest is complete, coral is cleaned using a solution of 50% hydrochloric acid and water. It is also cleaned and tumbled with sharp sand. From there it is cut, ground, sanded and polished.

The Critical Coral Reef:

It is the labor and high cost of turning this rough material into polished jewelry that makes coral pieces so expensive. Italian craftsmen are extraordinarily particular about the coral they use -- it must be free of fractures and blemishes. And transforming raw coral into fine jewelry is a painstakingly delicate process. It involves intricate sawing and proper heating to prevent cracks and discoloration. But the beautiful final results are well worth the time and effort. Though they cover less than 0.2% of the ocean floor, coral reefs are home to approximately 25% of the ocean's species. Do the math and that comes to roughly 5000 species of reef fish scattered among 2,500 species of coral! But unfortunately two-thirds of the world's reefs are perishing: 10% are degraded past recovery, while 30% are in critical condition and may die within ten to twenty years. This is unfortunate, because the corals protect the shorelines, make wonderful fish nurseries, and give food, shelter and protection to almost a million marine species. Fortunately, fishing for coral doesn't affect coral reefs. The species of coral that creates coral reefs is not the same species as the coral we wear in jewelry: the species that creates reefs in the South Pacific and Australia is corallium japonicum.

Coral Through The Years:

Coral beads and artifacts were found in the graves of pre-dynastic Egypt, from as far back as 4000 B.C., as well as in graves from the Iron Age, and in Neolithic sepulchers dating back to 10,000 B.C. Throughout the world, museums have coral collections of amulets and ornaments going as far back as 1000 B.C. In India, coral was as highly valued as the pearl was in Rome. The Persians particularly admired its color. The Chinese and the Hindus ornamented the figures of their gods with it, while in Tibet coral's red color was believed to be symbolic of one of the incarnations of Buddha. It was used as a personal ornament combined with turquoise and amber, and used to decorate temples. Its use was so prevalent that even Marco Polo remarked upon it in the 13th century. In Africa, coral was worshipped, and considered the most priceless gift a ruler could bestow. If a string of coral were lost or stolen, all those involved were summarily killed! The Gauls used it to ornament their helmets and weapons of war, and during the Christian era coral was believed of war, and during the Christian era coral was believed to possess sacred qualities, leading to a lively trade between the Mediterranean and India. Red was the favorite coral color of the Pueblo Indians of New Mexico and Arizona, as well as the Zuni and Hopi peoples. They retrieved it in the variously colored fragments of the spiny oyster shells taken from the Gulf of Mexico. Over the centuries, the world has continued to delight in coral. Both the Renaissance and the Victorian periods incorporated it into their fine jewelry. President Lincoln and many prominent Americans were extremely fond of it. In Europe, great rivalries even sprang up around coral: From Medieval times to the present, Europe and the Mediterranean have vied for the control of coral fishing rights along the African coasts. Today the main coral trade is in Italy, located mainly around Naples, Rome and Genoa.

Fun Facts About Coral:

Coral was thought to quiet the waves and made the sea calm. (Considering the fact that coral reefs protect the shoreline, that idea wasn't completely wrong!)
Coral was also thought to preserve against lightening and terrible tornadoes. Its power supposedly increased when exposed to the full moon
According to ancient lore, Perseus placed the severed head of Medusa in its bag on a heap of seaweed. The head's power passed into the seaweed, which turned as rigid and as shriveled as stone. The Sea Nymphs were delighted. They took armfuls of it back under the sea with them and brought fresh seaweed up to be turned to stone by the head of Medusa. Hence, we have coral.
The Romans believed coral to be a potent charm, and hung branches of coral around the necks of their children to preserve them from harm. They also pulverized it and mixed it with wine, as a cure-all tonic to be imbibed after their infamous debauches.
During the Medieval period coral was used as a cure for sterility and as charm against the evil eye.
Italian men presented coral jewelry to their beloved as a token of love and fidelity to signify that they were engaged.
A Native American husband in the Southwest presented red coral jewelry to his wife so that she might bear him many children.

Pearl Details

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Fresh Water Pearls:
Pearls are unique among gemstones, being the only ones found within a living creature and the only ones that requires no fashioning, (cutting or polishing,) before use. Another distinctive feature is its near exclusive use by one gender. Although some efforts have been made to market pearl jewelry to males in recent years, pearls remain the most "feminine" of all gemstones. Designated officially as the June Birthstone, it is, unofficially, a near requirement for brides. ... Cultured pearls are those that form in certain mollusks, (oysters and mussels,) at the intervention of man. A piece of mantle tissue, or a shell bead, is inserted into the interior of the animal. This causes it to secrete a layer of organic material, (conchiolin,) over the irritant, followed by layers of nacre (nay-ker.) The composition and structure of this nacre is essentially identical to that which forms under natural conditions. The thin layers of nacre create a kind of diffraction grating through which light must pass and are responsible for the surface iridescence, called orient, so admired in pearls. Pearls have both a body color and "overtones" of rainbow hues created by the orient. The culturing process takes place over a period of one to three years, depending on the conditions, the species and the desired outcome. ... The commercial process for raising freshwater pearls originated in Lake Biwa, Japan at the end of the 1920's. Various problems, such as pollution and viral diseases, have hampered production in recent years. Progress is being made in restoring the ecosystems and breeding resistant mollusks, so we should see a return of Japanese pearls to a prominent place in the market in the future. At present, however, the premier source is China.
Although once thought of as an inferior product, advances in technique and marketing practices have made today's Chinese freshwater pearl a true gem. The US continues to command a share of the market with the pearls produced from areas in the South, especially the Tennessee River. Culturing pearls is a delicate process, not assured of success - only 25 - 50% of the altered mollusks produce pearls and generally, only a small percentage of the pearls harvested are of gem quality. ... The natural range of colors in freshwater pearls is from white to tan to gray, depending primarily on the species that is used in production. Enhancements are so common that unless it is specifically stated by the seller, you should assume a pearl has been at least bleached to remove dark spots of conchiolin that show through the nacre. More dramatic techniques, such as dying or irradiation, produce pearls with exotic colors such as green, rose and lavender. ... Pearls are generally named by their shape; so we have baroques that can be any shape, stick pearls, button pearls, seed or rice pearls, rounds and drops. There are blister pearls, which are created by attaching a bead or other nucleus to the shell of the mollusk and then cutting it out after it has become nacreous. Mabe pearls are assembled from blister pearls, which are filled and glued to a shell base. The term "Keshi" has come to be used for just about any baroque pearl, but in its strictest sense refers to a pearl that spontaneously forms in the oyster during the culturing process, without mantle tissue or bead. ... Although pearls are delicate, they have been successfully used in jewelry for thousands of years. As they are sensitive to heat, chemicals and abrasion, they should be stored in a cloth bag or their own box away from contact with other materials. They should be protected from chemicals such as hairspray and perfume. Wiping them with a damp cloth after wearing and occasional cleaning in mild soapy water is all that's required. Under no circumstances should they be placed in an ultrasonic or steam cleaner. Jewelry settings in rings and bracelets should be protective, or if not, (as in many pearl rings,) the piece should be considered for occasional use only, rather than daily wear. ... Faux pearls have been around for a long time and can consist of a variety of materials such as glass, plastic or shell with various surface treatments meant to simulate the pearls luster. With cultured pearl prices at historic lows, there is little incentive to buy or wear imitations. A rule of thumb when testing a suspect pearl is to rub it across the surface of your teeth. Real pearls will feel slightly gritty, most imitatons will feel smooth.

Value:
The value of a pearl is most related to the thickness and quality of the nacre. Other factors include size, (especially in rounds) shape, and color. In general, the highest prices will be paid for large, round, well colored, unenhanced gems. Factors that influence value in pearl jewelry pieces would add to these general considerations, quality of stringing and degree of matching in size and color.

Salt Water Pearls:
Pearls are one of our most ancient gems with records of commercial harvesting going back 2500 years. Their natural occurrence is very rare, with only one in several million shellfish ever producing a pearl. Oysters are the best-known source, but clams, mussels, and abalone also produce pearls.... For a pearl to form an irritant, (usually a grain of sand,) must get deep enough inside a shell, that the animal cannot expel it. The creature's shell producing system begins coating the irritant with nacre, the shiny substance that you find on the interior of most shells.... Nacre is composed of the mineral aragonite, with an organic binder called conchiolin. The aragonite forms minute crystals with a radial oriented, concentric structure. You can feel the edges of these crystals by rubbing a pearl against your teeth. The tooth test has long been used for pearls. Most of their imitations will feel smooth, rather than gritty, when rubbed against a tooth.
Natural pearls almost disappeared from the market in the late 1800's due to excessive harvesting. Even today, they are extremely rare and demand a huge ransom. Necessity is the mother of invention and, as pearl sources began to dry up, several enterprising Japanese developed methods of culturing pearls in oyster farms.... Cultured pearl production began in Japan around 1910. Not only does the culturing process provide more pearls, it also allows larger pearls to be produced. ... The process involves inserting a mother of pearl seed, along with a piece of tissue, known as the mantel, into the oyster. After surgery, the oysters convalesce in a "hospital" for four to six weeks. They are then transferred to cages between seven and ten feet under water. Here, they are allowed to grow for three to six years. ... Freshwater pearl farms began in Lake Biwa, Japan around 1928. They have the advantages that up to thirty seeds can be inserted in a single clam and the production time is just three years. The term "Biwa" is nearly synonymous with freshwater pearls, but one should be careful about using it if the source is unknown.... Freshwater pearl shapes were originally quite irregular, but steady improvements have been made. Today, freshwater pearls rival their saltwater cousins in shape and luster. When grading pearls, it makes no difference if they are from fresh or salt water. ... Unfortunately, pollution and illness have greatly reduced the Japanese saltwater farms in recent years. However, freshwater farming is on the rise. Freshwater pearls are being grown all around the world and the quality is constantly improving.

Facts about Pearls:
CHEMISTRY CaCO3 (aragonite, the outer layer) about 82 - 86%, conchiolin 10 - 14%, water 2%. CRYSTALLOGRAPHY Aragonite is orthorhombic, with crystals radially oriented.
REFRACTIVE INDEX 1.53 - 1.69
HARDNESS 2.5 - 4.5
SPECIFIC GRAVITY 2.6 - 2.78.
CLEAVAGE None
HEAT SENSITIVE Yes
WEARABILITY* Good

SPECIAL CARE INSTRUCTIONS Avoid heat and all chemicals, including perfume and other cosmetics.

ENHANCEMENTS Dying, common

Ruby Details

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Ruby:
Ruby is red corundum, all other color varieties of corundum being referred to as sapphire. The ruby color range includes pinkish, purplish, orangey, and brownish red depending on the chromium and iron content of the stone. The trace mineral content tends to vary with the geologic formation which produced the ruby, so original place designations such as Burmese and Thai have come in later years to be sometimes used in describing color.... Most authorities expect a medium to medium dark color tone in a ruby, naming stones lighter than this, pink sapphire -- but there is no general agreement exactly where the line is to be drawn. The old joke about questionable stones goes: "Whether it's a ruby or a pink sapphire depends on whether you're the buyer or the seller." ... All corundum gems including ruby have a long history of enhancement. Unless the seller specifically states the stone is unheated, you should assume that some kind of heat treatment has been used. Usually high temperature heating and controlled cooling is done to clarify the stones, especially by dissolving "silk" (rutile); but it can also improve tone and saturation of color. Such treatments can only be detected in stones whose residual inclusions show signs of heat stress; truly clean stones will give no clues and cannot be verified as natural color. The general view at present seems to be that simple heating, being indistinguishable from Nature's own heating processes, and stable, is acceptable -- as long as it is disclosed. For this reason such enhancement does not radically lower the value of ruby gems. Not so for other more recently invented treatments such as diffusion coloring, or polymer or glass filling. ... Corundum was first synthesized in the early 1900's by a simple flame fusion process. Many jewelers and gemologists have had the unpleasant task of telling the proud heir that Grandmother's treasured ruby ring or brooch contains a flame fusion stone and has a lot more sentimental than commercial value. More complex synthesis processes have been developed in recent years. These so closely simulate natural formation conditions that colors and even inclusions look extremely natural and such stones are difficult for all but the most highly skilled professionals to identify as man-made. ... Ruby is hard (9) and tough, making it a superb jewelry stone. (Of course, a heavily included or fractured stone will be less stable.) For reasonably clean stones, no special wear or care precautions are necessary. Ruby shows pleochroism which means that the color varies with the direction of viewing. Most stones show purplish red and orangey red, although the presence or absence of trace minerals can dampen either of these. The overall color can often, but not always, give a clue to a stone's geographic origin, with Burmese stones tending to purplish red colors and Thai stones appearing more brownish red. In addition, many rubies will fluoresce in long or short wave UV and this property can often be used to help identify a stone's geographic origin. Burmese rubies often fluoresce so strongly that the effect is noticeable even in sunlight, such stones seem literally to glow, and are greatly admired. Thai stones generally lack this property. Although Asia has historically been the major producer of ruby gems, there are many other sources including the USA, Australia, and most recently Africa. ...Ruby rough of lower quality is used in great quantities to make beads, carvings, and other ornamental objects. The silk, which is so common in corundum, can, if sufficiently abundant, and precisely arranged, lead to asterism. With proper cutting, this creates star rubies. Today there are heating and diffusion processes that can increase the rutile content and improve such gems. Synthetic star corundums were very popular in the 1950's under the trade name "Linde Stars" and are still under production. ... Few other gems have as much myth, lore and romance surrounding them, with one of the chief attractions being the protection from misfortune and bad health rubies were believed to afford their lucky owners. As the science of gemology developed it became known that many historically important "rubies" such as the famed Black Prince's Ruby of the British Crown Jewels, were actually other red gems, most often red spinels.

Value:
Rubies are the most valuable members of the corundum family. Large gem quality rubies can be more valuable than comparably sized diamonds and are certainly rarer. There is a relative abundance of smaller, (1-3 carat,) blue sapphires compared to the scarcity of even small gem quality rubies, making even these smaller stones relatively high in value.... Stones of Burmese origin generally command the highest prices. The vast majority of rubies are "native cut" in the country of origin. High value ruby rough is tightly controlled and rarely makes its way to custom cutters. Occasionally, such native stones are recut to custom proportions, albeit at a loss of weight and diameter. Custom cut and recut stones are usually more per carat, and my own bias is that they are worth it. ... Sinkankas and Miller in the Standard Catalog of Gem Values, 2nd. Ed. list a wide range of wholesale prices for faceted gem rubies. Prices are dependent on origin, color, size, and clarity: from a low of $100 to $15,000/ ct maximum. ... Burmese stones in 1/2 to 1 ct sizes with slightly purplish red color and light inclusions range from $300 to $3000/ ct, for example. The price survey done by the International Gem Society reports that clean, top color gems in the 1/2 to 1 ct size range are being sold, retail, on the Internet with a range of $1000 - $3000/ct.

Facts about Rubies:
CHEMISTRY Al2O3
CRYSTALLOGRAPHY Hexagonal
REFRACTIVE INDEX 1.757 - 1.779
HARDNESS 9
SPECIFIC GRAVITY 3.99 - 4.0
CLEAVAGE None
HEAT SENSITIVE No

WEARABILITY* Excellent:
SPECIAL CARE INSTRUCTIONS None

ENHANCEMENTS:
Heat treated. Common. Fractures filled, occasional.

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