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Chiangmai Gems Gallery, the World Biggest Jewelry Store: Free Transportation call: Patrick 081 617 2116 (Overseas call +66 81 617 2116)เพ็ญนภา (แก้ว) 081 498 0613(จากต่างประเทศ +66 81 498 0613)
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Sapphire (Greek: σάπφειρος; sappheiros, "blue stone"[1]) is a gemstone variety of the mineral corundum, an aluminium oxide (α-Al2O3), when it is a color other than red or dark pink, in which case the gem would instead be called a ruby, considered to be a different gemstone. Trace amounts of other elements such as iron, titanium, or chromium can give corundum blue, yellow, pink, purple, orange, or greenish color. Pink-orange sapphires are also called padparadscha. Pure chromium is the distinct impurity of rubies. However, a combination of e.g. chromium and titanium can give a sapphire of a color distinct from red.
Sapphires are commonly worn as jewelry. Sapphires can be found naturally, by searching through certain sediments or rock formations, or they can be manufactured for industrial or decorative purposes in large crystal boules. Because of the remarkable hardness of sapphires (and of aluminum oxide in general), sapphires are used in some non-ornamental applications, including infrared optical components, such as in scientific instruments; high-durability windows (also used in scientific instruments); wristwatch crystals; and very thin electronic wafers, which are used as the insulating substrates of very special-purpose solid-state electronics (most of which are integrated circuits).
Natural sapphires
An uncut/rough yellow sapphire found at the Spokane Sapphire Mine near Helena Montana
The sapphire is one of the two or three gem-varieties of corundum, with another one being the red or deep pink ruby. Although blue is their most well-known color, sapphires are made up of any color of corundum except for red (red ones are called rubies).[2] Sapphires may also be colorless, and they are also found in shades of gray and black.
The cost of natural sapphires varies depending on their color, clarity, size, cut, and overall quality – as well as their geographic origin, oddly enough. Significant sapphire deposits are found in Eastern Australia, Thailand, Sri Lanka, Madagascar, East Africa, and in North America in a few locations, such as at "Gem Mountain", and in or near the Missouri River in the region around Helena, Montana.[3] Sapphire and rubies are often found together in the same area, but one gem is usually more abundant.[4]
Chiangmai Gems Gallery: Free Transportation call: Patrick 081 617 2116 (Overseas call +66 81 617 2116)
เพ็ญนภา (แก้ว) 081 498 0613(จากต่างประเทศ +66 81 498 0613)
e-mail: neomart@gmail.com
Blue sapphire
The 423-carat (85 g) blue Logan sapphire
Color in gemstones breaks down into three components: hue, saturation, and tone. Hue is most commonly understood as the "color" of the gemstone. Saturation refers to the vividness or brightness or "colorfulness" of the hue, and tone is the lightness to darkness of the hue.[5] Blue sapphire exists in various mixtures of its primary (blue) and secondary hues, various tonal levels (shades) and at various levels of saturation (brightness).
Blue sapphires are evaluated based upon the purity of their primary hue. Purple, violet, and green are the most common secondary hues found in blue sapphires.[6] Violet and purple can contribute to the overall beauty of the color, while green is considered to be distinctly negative. Blue sapphires with up to 15% violet or purple are generally said to be of fine quality. Blue sapphires with any amount of green as a secondary hue are not considered to be fine quality. Gray is the normal saturation modifier or mask found in blue sapphires. Gray reduces the saturation or brightness of the hue and therefore has a distinctly negative effect.[6]
The color of fine blue sapphires can be described as a vivid medium dark violet to purplish blue where the primary blue hue is at least 85% and the secondary hue no more than 15% without the least admixture of a green secondary hue or a gray mask.[5]
The 423-carat (85 g) Logan sapphire in the National Museum of Natural History, in Washington, D.C., is one of the largest faceted gem-quality blue sapphires in existence.
Fancy color sapphire
Pink sapphireYellow and green sapphires are also commonly found. Pink sapphires deepen in color as the quantity of chromium increases. The deeper the pink color the higher their monetary value as long as the color is trending towards the red of rubies.
Sapphires also occur in shades of orange and brown, and colorless sapphires are sometimes used as diamond substitutes in jewelry. Padparadscha sapphires often draw higher prices than many of even the finest blue sapphires. Recently, more sapphires of this color have appeared on the market as a result of a new artificial treatment method that is called "lattice diffusion".[7][8]
Padparadscha
Faceted padparadscha
Padparadscha is a pink-orange corundum, with a low to medium saturation and light tone, originally being mined in Sri Lanka, but also found in deposits in Vietnam and Africa; Padparadscha sapphires are very rare and highly valued. The name derives from the Sinhalese word for lotus blossom.[9] Along with rubies, they are the only type of corundum to be given their own name instead of being called a particular colored sapphire. Padparadscha used to be a subvariety of ruby.[10] The rarest of all padparadschas is the totally natural variety, with no sign of treatment.
Star sapphire
Thai Black Star Sapphire...The 182 carats (36 g) Star of Bombay star sapphire
A star sapphire is a type of sapphire that exhibits a star-like phenomenon known as asterism. Star sapphires contain intersecting needle-like inclusions (often the mineral rutile, a mineral composed primarily of titanium dioxide[11]) that cause the appearance of a six-rayed "star"-shaped pattern when viewed with a single overhead light source.
The Black Star of Queensland is believed to be the largest star sapphire that has ever been mined, and it weighs 733 carats.[12] The Star of India (weighing 563.4 carats) is thought to be the second-largest star sapphire, and it is currently on display at the American Museum of Natural History in New York City. The 182-carat Star of Bombay, located in the National Museum of Natural History, in Washington, D.C., is an example of a blue star sapphire. The value of a star sapphire, however, depends not only on the weight of the stone but also the body color, visibility and intensity of the asterism.
Chiangmai Gems Gallery, the World Biggest Jewelry Store: Free Transportation call: Patrick 081 617 2116 (Overseas call +66 81 617 2116)
เพ็ญนภา (แก้ว) 081 498 0613(จากต่างประเทศ +66 81 498 0613)
e-mail: neomart@gmail.com
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เพ็ญนภา (แก้ว) 081 498 0613(จากต่างประเทศ +66 81 498 0613)
E-mail: neomart@gmail.com
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