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Ceylon Sapphires - Montana Sapphires - Blue Sapphire
Fancy Color Sapphires - Star Sapphire - Yogo Sapphires
The Gemstone Sapphire
Composition: Aluminum Oxide
Class: Oxides and Hydroxides
Crystal System: trigonal; bar 3 2/m
Specific Gravity: 3.99 - 4.0
Refractive Index: 1.757 - 1.779
Luster: vitreous to adamantine
Color: Most any color some stones show zoning
Cleavage: is absent, although there is parting which occurs in three directions
Transparency: Crystals are transparent to translucent
Associated Minerals: calcite, feldspars, garnets, micas and zoisite
Heat treating is Common. Diffusion treatment is done occasionally. Diffusion places a thin blue coating on colorless sapphire. Irradiation is rarely used. Irradiation turns colorless gems yellow, orange or light blue.
Birthstone for September:
Sapphire is often considered to be synonymous with the color blue. However, sapphie comes in every color but red. Red is called ruby. The other colors of sapphire can be just as beautiful and rare. Or even more rare than blue. Some are even considered to be collectors items. However, they are usually priced less. Yellow, orange, lavender, and other pastel shades are especially affordable.
The International Colored Gemstone Association has passed a resolution that the light shades of the red hue should be included in the category ruby since it was too difficult to legislate where red ended and pink began. In practice, pink shades are now known either as pink ruby or pink sapphire. Either way, these gems are among the most beautiful of the corundum family.
The ancient Persians believed that the earth rested on a giant sapphire whose reflection gave the sky its color. Damigeron, a historian of old, wrote that sapphire was worn by kings to protect them from harm. It was also believed that sapphire would protect the wearer from envy and attract divine favor. The gem was regarded as a symbol of truth, sincerity and constancy.
Legend has it that if a poisonous snake were put into a vessel along with a sapphire, the rays from the gem would kill it. Our ancestors interpreted this to mean that sapphire was an antidote against poison.
At one time. Any blue gem material was called sapphire. References to a blue-flecked stone, led mineral experts to realize that some of what had been called "sappheiros" was actually lapis lazuli. "Sappheriros" is Greek for "blue." From the Mountains of Kashmir The finest sapphire color is rich, velvety cornflower blue. This is called "kashmir" out of the deference to the traditional source of the finest quality.
Today, however, the Kashmir area of India is not generally mined because of its physical inaccessibility. Most current production comes from Sri Lanka, Burma, Thailand, Montana, Australia and Africa.
The most valuable other fancy sapphire is a orange-pink or pinkish-orange called "padparadscha" after the lotus blossom. Padparadscha sapphires are very rare and the exact definition has always been a matter of debate: different dealers and different laboratories around the world disagree on the exact color described by this term. Some dealers even argue that the term should not be limited to the pastel shades of Sri Lankan sapphires but should also include the more firey shades of reddish-orange from the Umba Valley in Tanzania.
have fine, needle-like inclusions called asterism. When these inclusions are numerous enough to make the stone translucent or opaque and are oriented properly, they allow light to be reflected in such a way that a moving star forms across the top of the stone. When a cutter recognizes this potential in a piece of rough sapphire, he will cut it in a dome shape. Stars are not visible in faceted stones.
The Sinhalese believed the star sapphire would protect them against witchcraft. The three intersecting rays were thought to represent faith, hope and destiny. Museums the world over exhibit star sapphires that are noteworthy for size or quality. The 543-carat "Star of India" resides in the Morgan-Tiffany Collection in the American Museum of Natural History in New York City.
Major Deposits and Characteristic Colors:
Africa has numerous deposits of gem quality corundum and has recently been a source of new sapphire and ruby discoveries.
Umba River: Some blue, lavenders and purples to plums, yellows, golds to orange browns, pinks, and padparadschas.
Songea: Deep red rubies, blues, blue greens, greens, yellows, pinks, alexandrite-type Or color change (blue in sunlight and fluorescent light, lavender to purple in incandescent).
Tunduru: Full spectrum of colors.
Blue, very much like Sri Lankan blue. The rubies are clear red and often unheated. Range of pink from pale to intense.
Lodwar: - Clear deep blue to very dark blue-green and an abundance of opaque blue stars.
Garbatula: deep, blackish blue-green to intense pleasant green.
The island nation south of India was known as Ceylon for many generations. Consequently "Ceylon-blue" is a color name outliving the change in national name. Sapphires of note in large sizes - over 5 carats - of outstanding color are predominantly of Sri Lankan origin. White, blue, purple, pink, yellow, gold, and padparadaschas.
Ruby and sapphire mines of Burma are legendary and have produced some of the world's finest rubies and blue sapphires.
Mogok Stone Tract
Star rubies, star sapphires, rubies. Sapphire - violet, yellow, color-change, and blue.
Thailand is a traditional supplier of sapphire and ruby. The majority of sapphire production from the Kanchanaburi field has been mined in the last ten years. This deposit is approaching depletion.
blue, rubies, dark blue, green, yellow, and black star - 6 and 12 ray.
blue and green, yellow and rubies.
Rubies and sapphires have been found in Vietnam since the late 1980's. They are very rarely seen in the jewelry market.
Luc Yen & Quy Chau:
red and red-pink rubies, hot pink and purple sapphire.
PAILIN - blue sapphire and color change ruby.
Australia also has several deposits and contributes greatly to the sapphire jewelry market in mostly Inky blues to less known brilliant true blues, green, blue-green, yellow-green, yellows, oranges, and some pinks.
Montana is the major US source and has four main deposits.
Dry Cottonwood Creek:
yellow, gold and green, some pink, blue, and very, very rarely a ruby.
green, blue, yellow, orange, pink, and very rarely ruby.
full spectrum of colors including many bicolors, and also very rarely ruby.
blue and purple.