Colorful choices in colored Gemstones
The big three; Emerald, Ruby, and Sapphire
- Emerald
Emerald is the green variety of the mineral beryl and one the most highly prized of all the gems. Emerald aside from being the birthstone for May, it was historically believed to bestow on its wearer faithfulness and unchanging love, and was thought to enable the wearer to forecast events.
The highest quality emerald has the color of fresh young green grass; an almost pure spectral green, possibly with a very faint tint of blue, as in the finest emerald from Colombia, which is considered by connoisseurs to be the world's finest. Flawless emeralds are rare, so their "flaws" have come to serve almost as "fingerprints," while flawless emeralds are immediately suspect. Although a hard stone, emerald will chip easily since it tends to be somewhat brittle, so special care should be given in wearing and handling.
Because of emerald's popularity and value, imitations are abundant. Glass, manufactured complete with "flaws," and doublets or triplets, like "aquamarine emeralds" and "Telca emeralds," are often encountered. New products such as the "Lannyte Emerald Doublet" are also entering the market; when properly represented, they can make an interesting jewelry choice, but a second or third party may fail to mention that they are "doublets."
Also, fine synthetic emeralds are being produced with nearly the same color, hardness, and brilliance as genuine emerald. These synthetics are not inexpensive themselves, except by comparison to a genuine emerald of equivalent quality.
Techniques are enhance color and reduce the visibility of flaws are frequently used. A common practice is to boil the emerald in oil (sometimes tinted green), a practice that goes back to early Greek times. This is a widely accepted trade practice, since it is actually good for the stone in light of its fragile nature. Oiling hides some of the whitish flaws, which are actually cracks, filling the cracks so they become less visible. The oil becomes an integral part of the emerald unless it is subjected to some type of degreasing procedure. The development and use of the ultrasonic cleaner has brought to light the extensiveness of this practice. Never clean emeralds in an ultrasonic cleaner.
Oiling is considered an acceptable practice, but be sure the price reflects the actual quality of the stone. If necessary, most emeralds can be "re-oiled."
As with all highly desired gems, the greater the value and demand, the greater the occurrence of fraudulent practices. Examples of almost every type of technique to simulate emerald can be found; color alteration by using green foil on closed backs, use of synthetics, substitution of less valuable green stones, doublets, or other composites, etc. Therefore, be especially cautions of bargains, deal with reputable jewelers when planning to purchase an emerald gemstone, and always have a the purchase double checked by a qualified gemologist appraiser.
- Ruby
Ruby prized through the ages, even by kings, as the "gem of gems ... surpassing all other precious stones in virtue," ruby is the red variety of the mineral corundum. Historically, ruby has been symbolic of love and passion, considered to be an aid to firm friendship, and believed o ensure beauty. Today, ruby is birthstone for July, ruby's color ranges from purplish or bluish red to a yellow red. The finest color is a vivid, almost pure spectral red with a very faint undertone of blue, as seen in Burmese rubies, which are considered the finest. The ruby is very brilliant and very hard, ranking 9 on Moh's scale (an internationally recognized standard that ranges from 1 for very soft to 10 the very hardest). Ruby is also very durable and wearable, characteristics that make it an unusually fine choice for any piece of jewelry.
Translucent varieties of ruby are also seen, and one variety exhibits a six-ray star effect when cut as a cabochon. This variety is called star ruby and is one of nature's most beautiful and interesting gifts. But, as with so many other beautiful gifts once produced only in nature, these lovely gems are now duplicated in synthetic star rubies, and numerous "faked" star rubies are also the products of mankind's attempts at mimicry.
Again, remember that the greater the value and demand, the greater the use of techniques to "improve" or simulate. Among rubies, as among other gemstones, examples of almost every type of deceptive technique can be found; color enhancement, synthesis, substitutes, doublets, triplets, misleading names, and so on. The newest laboratory gown synthetic rubies, like those made by Ramaura and Chatham, are so close to natural ruby in every aspect that many are actually passing for genuine, even among gemologists. When getting a very fine, valuable ruby, be sure to verify genuineness with a gemologist who has both many years' experience in colored gems and an astute knowledge of marketplace today. We would also recommend having the jeweler or gemologist also obtain a colored gemstone report from a major gem testing laboratory.
Here again, be especially cautious of bargains. Deal with reputable jewelers when planning to purchase a ruby gemstone, and have the purchase double checked by a qualified gemologist appraiser.
- Sapphire
Sapphire the "celestial" sapphire, symbol of the heaven, guardian of innocence, bestower of truth and good health, preserver of chastity, is in fact the mineral corundum. While we know it best in its blue varieties, which is highly prized, it comes in essentially every color; red corundum is ruby. As with with ruby, its sister gemstone, sapphire is characterized by hardness, brilliance, and availability in many beautiful colors, all of which make it probably the most important and most versatile of the gem families.
Blue sapphires can be among the most valuable members of the sapphire family; especially stones from Burma and Kashmir, which closet to the pure spectral blue. Fine, brilliant, deep blue Burmese sapphires will surely dazzle the eye and the pocketbook, as will the Kashmir, which is a fine velvety toned deep blue. Many tend to be too dark, however, because of presence of too much black and pure cuttin (cutting deep for additional weight), but the deep blues can be treated to lighten the color.
The Ceylon (Sir Lanka) sapphires are a very pleasing blue, but are a less deep shade than the Burmese or Kashmir, instead tending yo fall more on the pastel side.
We are also seeing many Australian sapphires, which are often a dark blue, but with a slightly green undertone, as are those from Thailand; both sell for much less per carat. They offer a very affordable alternative to the Burmese, Kashmir, or Ceylon, and can still be very pleasing in their color. Blue sapphires also come Tanzania, Brazil, Africa, and even United States. Montana sapphires are very collectible because of their unusual shades of color, and because many are natural color, that is not subjected to any treatment. For those who want a gem that is truly "natural,: Montana sapphire may be the choice for you.
With sapphires, origin can have a significant effect on price, so if you are purchasing a Kashmir, Burmese, or Ceylon sapphire, that should be noted on the bill of sale.
Like ruby, the blue sapphire may be found in a translucent variety that may show a six rayed star effect when cut into a cabochon. This variety is known as star sapphire, of which there are numerous synthetics (often referred to the trade as "Linde," pronounced Lin' dee).
In addition to blue sapphire, we are now seeing the appearance of many other color varieties in the latest jewelry designs; especially yellow and pink, and in smaller sizes some beautiful shades of green. These are known as fancy sapphires. Compared to the cost of blue sapphire and ruby, these stones offer excellent value and real beauty.
A beautiful and variety called padparadscha (a type of lotus flower) is also in demand. The true padaradshca should exhibit a pink and orange color simultaneously. Depending upon richness of color, brilliance, and size, these can be very expensive. A lovely but more common and more affordable variety is available today which is really a rich orange color. It is often sold as padaradscha but the rarer and more costly gem will always exhibit a strong pink with the orange.
Inevitably, evidence abounds of every technique known to improve the perceived quality and value of the sapphire; alteration of color, synthesis, composites, and misleading names. Techniques have been developed to treat natural sapphires to remove a certain type of flaw (needle inclusions) and to change the color; for example, to create a "Ceylon" sapphire that never came from Sri Lanka but whose color looks like that of a Ceylon. Be especially alert to the new diffusion treated blue sapphire, which is blue on the surface only. Also, watch out for the new true doublets flooding the market. As always, we urge you to be especially cautious of bargains, deal with reputable jewelers, and have your gemstone double checked by a qualified gemelogist appraiser.
Other popular colored gems
- Alexandrite
Alexandrite is a fascinating transparent gem that appears grass green in daylight and raspberry red under artificial light. It is a variety of chrysoberyl reputedly discovered in Russia in 1831 on the day Alexander II reached his majority; hence the name. In Russia, where the national colors also happen to be green and red, it is considered a stone of very good omen. It is also considered Friday's stone or the stone of "Friday's child."
Unlike other gemstones, which mankind has known about and admired for thousands of years, Alexandrite is a relatively recent gem discovery. Nonetheless, it has definitely come into its own and is presently commanding both high appeal and high prices. While fairly common in small sizes, it has becomes relatively scarce in sizes of two carats or more. If you see an alexandrite that measures more than half inch in width, be suspicious of a fake. Alexandrite is normally cut in a faceted style, but some cat's eye type alexandrite, found in Brazil, would be cut as cabochon to display the eye effect. These are usually small; the largest have been seen was approximately three carats.
Prior 1973, there was really no good synthetic alexandrite. While some varieties of synthetic corundum and synthetic spinel were frequently sold as alexandrite, they really didn't look like the real thing but were hard to differentiate since so few buyers had ever seen genuine stones. They are, however, easy for a gemologist to spot. In 1973 a very good synthetic alexandrite was produced, which is not easy to differentiate from natural stones. While a good gemologist today can identify the synthetics, when they first appeared on the market many were mistaken for real one. Be especially careful to verify the authenticity of your alexandrite, sine it might have been mistakenly identified years ago, and passed along as authentic to you.
- Amber
Amber is not a stone, but rather an amorphous, fossilized tree sap. It was one of the earliest substances used for personal adornment. Modestly decorated pieces of rough amber have been found in Stone Age excavations and are assumed to have been used as amulets and talismans; a use definitely recorded throughout history before, during, and since the ancient Greeks. Because of its beautiful color and the ease with which it could be fashioned, amber quickly became a favorite object of trade and barter and personal adornment. Amber varies from transparent to semi-translucent, and from yellow to dark brown in color; occasionally it's seen in reddish and greenish brown tones. In addition, amber can be dyed many colors. Occasionally, on can find "foreign" fragments or insects that were trapped in the amber, which usually increases its value because of the added curiosity factor.
Plastics are the most common amber imitations. But real amber, which is the lightest gem material, may be easily distinguished from most plastic when dropped into a saturated salt solution; amber will float while plastic sinks. One other commonly encountered "amber" type is "reconstructed" amber; amber fragments compressed under heat to form a larger piece. An expert can differentiate this from the real one under magnification.
Amber can be easily tested by touching it in an inconspicuous place with a hot needle (held by a tweezers). The whitish smoke that should be produced should smell like burning pine wood, not like medicine or disinfectant. If there is no smoke, but a black mark occurs, then it is not amber. Another test is to try to cut a little piece of the amber with a sharp pointed knife, at the drill hole of the bead; if it cuts like wood (producing a shaving), it is not amber, which would produce a sharp, crumbly deposit.
With the exception of those pieces possessing special antique value, the value of amber fluctuates with its popularity, which in part is dictated by the fashion industry and the prevalence of yellow and browns in one's wardrobe. Nonetheless, amber has proved itself an ageless gem and will always be loved and admired.
- Amethyst
Amethyst, a transparent purple variety of quartz, is one of the most popular of the colored stones. Once believed to bring peace of mind to the wearer, it was also thought to prevent the wearer from getting drunk, and if the circle of the sun or moon was engraved thereon, amethyst was believed to prevent death from poison.
Available in shades from light to dark purple, this February birthstone is relatively hard, fairly brilliant, and overall a good, versatile, wearable gemstone, available in plentiful supply even in very large sizes (although large sizes with deep color are now becoming Scarce). Amethyst is probably one of the most beautiful gemstones available at a moderate price; buyers should be careful, however, because "fine" amethyst is being produced synthetically today. Most synthetic can be identified by a skill gemologist.
Amethyst may fade from heat and strong sunshine. Guard your amethyst from these conditions and it should retain its color indefinitely. However, complaints have been heard of newly purchased amethyst jewelry fading over just a few months, from deep purple to light lavender. This should not happen, and may result from and unacceptable color treatment. If your gemstone fades this quickly, return it your jeweler.
- Andalusite (Poor Man's Alexanderite)
Andalusite (Poor Man's Alexanderite) is now offering interesting new possibilities for jewelry. Brazil is the primary source of these fascinating, fairly hard, and fairly durable gemstones. Andalusite is very interesting because it may exhibit several colors; an olive green in one direction, a rich reddish brown from another direction, and grayish green from yet another direction. In an emerald cut it may look primarily green while exhibiting an orange color at the ends of the emerald shape. In a round cut you may see the green body color with simultaneous flashes of another color. One benefit andalusite has over alexandrite is that you don't have to change the light in which it is being seen to experience its colors; merely changing the perspective does the trick. A rare and sometimes expensive emerald green variety may exhibit a bright yellow simultaneously, or when viewed from different angles. A pink variety does not exhibit this kind of color phenomenon. While andalusite is not readily available yet, it is finding a market, especially among men.
- Aquamarine
To dream of aquamarine signifies the making of new friends; to wear aquamarine earrings brings love and affection. Aquamarine, a universal symbol of youth, hope, and health, blesses those born in March. (Prior to the 15th century it was considered to be the birthstone for those born in October.)
Aquamarine is a member of the important beryl family, which includes emerald, but aquamarine is less brittle and more durable than its green counterpart. Aquamarine ranges in color from light blue to bluish green to deep blue, the later being the most valuable and desirable. It is a very wearable gem, clear and brilliant, and unlike emerald, is available with excellent clarity even in large sizes, although these are becoming scarce today. Aquamarines are still widely available in sizes up to 15 carats, but 10 carats sizes with fine color and clarity are becoming scarce and are more expensive. Long considered a beautiful and moderately priced gem, it is now entering the "expensive" classification for gemstones in larger sizes with a deep blue color.
Several words of caution for those interested in this lovely gem. First, you may want to think twice before buying a pale or shallow cut stone, since color will become paler as dirt accumulates on the back. These gemstones need constant cleaning to keep them beautiful. Second, be careful not to mistake blue topaz for aquamarine. While topaz is an equally beautiful gem, it is usually much less expensive since it is usually treated to obtain its desirable color. For those who can't afford an aquamarine, however, blue topaz is an excellent alternative; as long as it is properly represented and priced. Finally, note that many aquamarine colored synthetic spinels are erroneously sold as aquamarine.
- Benitoite
Benitoite, an exquisitely beautiful and rare gem is seldom seen in jewelry, but is very popular among collectors and connoisseurs. Discovered in San Benito, California; hence the name benito-it was recently selected as the official state gemstone of California and we are beginning to see more of it in fine jewelry houses there.
Benitoite ranges from colorless to dark blue (often with a violet tint) to violet. A rare pink variety has been identified. Benitoite can display "fire," the dispersion of white light into the rainbow colors, comparable to a diamond, and is also very brilliant. It lacks diamond's incredible hardness, however, and is more comparable to amethyst or tanzanite in hardness. It is difficult to find benitoite in sizes over one carat; only about five stones per year are cut which weigh two carats or more; only one every five years yields a stone five carats or more. Benitoite's rarity keeps it very expensive; a fine one carat gemstone could easily cost $3,000; and two carats size with fine color are extremely rare and even more costly. The largest fine benitoite known weighs just over 7-3/4 carats, and is on display at the Smithsonian Institution in Washington, D. C.
For jewelry, benitoite is a relatively wearable gemstone, but given its rarity and value, we recommend that it be set in a somewhat protective mounting so that it is not easily subjected to accidental scratching or wear.
- Beryl (Golden Beryl and Morganite)
As early as A. D. 1220 the virtues of beryl (Golden Beryl and Morganite) were well established in legend. Beryl provided help against foes in battle or litigation, made the wearer unconquerable, but at the same time friendly and likable, and also sharpened the wearer's intellect and cured laziness. Today beryl is considered important, but primarily for aesthetic reasons. The variety of colors in which it is found, its wonderful clarity (except for emerald), its brilliance, and its durability (again with the exception of emerald) have given the various varieties of beryl tremendous appeal.
Most people are familiar with the blue variety of beryl, aquamarine, and the green variety, emerald. Few as yet know the pink variety, morganite, and the beautiful yellow to yellow green variety, referred to as golden beryl. These gems have only recently found their place in the jewelry world but are already being shown in fabulous pieces made by the greatest designers. While not inexpensive, they still offer excellent value and beauty.
Beryl has also been found in many other colors; lilac, salmon, orange, sea green, as well as colorless. While most of these varieties are not as yet available to any but the most ardent rock hound, the orange varieties are fairly common and can still be found. Some orange varieties are heated to produce the more popular pink color and then sold as morganite.
The rarest color is red, which is even more rare than emerald, and comparable in cost. Until recently, it was known only to serious collectors and was called "Bixbite," after the man who discovered it. The gem variety of red beryl was discovered in Utah, still its only known source. But thanks to the discovery of anew deposit, we are now beginning to see this exciting gemstone in the jewelry market. It faces a major problem, however; what to call it. Some dealers are calling it "red emerald" because it is the same basic material as emerald and because it is truly comparable to emerald in rarity, beauty, and value. Whatever the name by which it is called; red emerald, red beryl, or "Bixbite," it is a beautiful gem that should be loved and cherished by anyone lucky enough to own one.
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