Blue Sapphire Information PDF

***Blue Sapphire **** LARGEST CONSUMERS: The US is the biggest market for sapphire, Other significant markets include Japan, Germany, Switzerland, Great Britain, and Taiwan. MOHS SCALE: 9 VARIERTY/ SPECIES/GROUP : Species: Corundum, COLOR/HUE RANGE/VALUE : very light to very dark violetish blue to g...

***Blue Sapphire **** LARGEST CONSUMERS: The US is the biggest market for sapphire, Other significant markets include Japan, Germany, Switzerland, Great Britain, and Taiwan. MOHS SCALE: 9 VARIERTY/ SPECIES/GROUP : Species: Corundum, COLOR/HUE RANGE/VALUE : very light to very dark violetish blue to greenish blue, highly valued sapphires are velvety blue to violetish blue, with medium to medium-dark tone w/strong to vivid saturation, commerical grade- greenish blue bodycolor or strong greenish blue pleochroism, color zoning, a grayish look, and very light or very dark tone. CHEMICAL COMPOSTION: it can grow in basaltic or non-basaltic environments, composed only of aluminum and oxygen and can grow in low concentrations of silicon, Non-basaltic sapphires form under a variety of conditions, primarily metamorphic FORMING SOURCE : Trace elements of iron and titanium create the blue, the more iron the corundum contains, the darker the blue, it can grow in basaltic or non-basaltic environments, CRYSTAL STRUCTURE : barrel- or spindle-shaped hexagonal pyramid or bipyramid POSSIBLE PHENOMENA : pleochroism ( slightly greenish blue and slightly violetish blue in different crystal directions) (When a cutter orients the table facet perpendicular to the optic axis direction, the finished stone’s face-up color displays more of the preferred violetish blue and less of the greenish blue hue.) CLARITY CHARACTERISTICS: color zoning is very common, silk (rutile needles), boehmite needles, included crystals, fingerprint inclusions, growth zoning, and color zoning and banding COMMON TREATMENTS : Heating and lattice diffusion are the most common treatments. Other treatments, used more rarely, are cavity and fracture filling with oil, epoxy resin, glass-like materials, or polymers; coating with various substances; and dyeing. Heating to improve color and clarity is by far the most common sapphire treatment COMMON CUTS: common to have deep pavilions, commonly in cushion and oval shapes with mixed cut, Trillion, emerald, pear, and marquise shapes are also available TRADE NAMES: “royal blue” ,“Kashmir”or “cornflower blue.” Kashmir is widely regarded as the finestquality blue sapphire, “Burmese” has a more intense blue hue then Kashmir but lacks the velvety luster and is still consider to be a very fine-quality sapphires -“Ceylon” and “Sri Lankan” lighter hue/ violetish blue to blue hue, with slightly grayish to strong saturation and receives more light return (equaling more brilliance) “Pailin” stones—from Pailin, Cambodia a basaltrelated sources -“Australian,” indicating a dark, inky color that sometimes appears silky or cloudy COUNTRIES OF ORIGIN: Non-basaltic Metamorphic sources include Myanmar, Kashmir, Sri Lanka, and most Madagascar deposits are finest sapphires Commerical Quality - Australia, China, Nigeria, Madagascar basalt-related high iron (aka darker blue) sapphire include Cambodia, Thailand, Australia, China, Nigeria, Vietnam, and some areas of Madagascar , Yogo Gulch, Montana, the sapphires are xenocrysts\ MAIN SYNTHETIC PROCESS : The most common method is flame fusion, others include flux, pulling, floating zone, and hydrothermal COMMON IMITATION MATERIAL : glass and synthetic spinel, Tanzanite, CUTTING/ TRADE CENTERS : Cutters in Thailand and India fashion most of the world’s sapphires