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Sapphire Biography & Facts

Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminium oxide (α-Al2O3) with trace amounts of elements such as iron, titanium, cobalt, lead, chromium, vanadium, magnesium, boron, and silicon. The name sapphire is derived from the Latin word sapphirus, itself from the Greek word sappheiros (σάπφειρος), which referred to lapis lazuli. It is typically blue, but natural "fancy" sapphires also occur in yellow, purple, orange, and green colors; "parti sapphires" show two or more colors. Red corundum stones also occur, but are called rubies rather than sapphires. Pink-colored corundum may be classified either as ruby or sapphire depending on locale. Commonly, natural sapphires are cut and polished into gemstones and worn in jewelry. They also may be created synthetically in laboratories for industrial or decorative purposes in large crystal boules. Because of the remarkable hardness of sapphires – 9 on the Mohs scale (the third hardest mineral, after diamond at 10 and moissanite at 9.5) – sapphires are also used in some non-ornamental applications, such as infrared optical components, high-durability windows, wristwatch crystals and movement bearings, and very thin electronic wafers, which are used as the insulating substrates of special-purpose solid-state electronics such as integrated circuits and GaN-based blue LEDs. Sapphire is the birthstone for September and the gem of the 45th anniversary. A sapphire jubilee occurs after 65 years. Natural sapphires Sapphire is one of the two gem-varieties of corundum, the other being ruby (defined as corundum in a shade of red). Although blue is the best-known sapphire color, they occur in other colors, including gray and black, and also can be colorless. A pinkish orange variety of sapphire is called padparadscha. Significant sapphire deposits are found in Australia, Afghanistan, Cambodia, Cameroon, China (Shandong), Colombia, Ethiopia, India Jammu and Kashmir (Padder, Kishtwar), Kenya, Laos, Madagascar, Malawi, Mozambique, Myanmar (Burma), Nigeria, Rwanda, Sri Lanka, Tanzania, Thailand, United States (Montana) and Vietnam.: 431–707  Sapphire and rubies are often found in the same geographical settings, but they generally have different geological formations. For example, both ruby and sapphire are found in Myanmar's Mogok Stone Tract, but the rubies form in marble, while the sapphire forms in granitic pegmatites or corundum syenites.: 403–429  Every sapphire mine produces a wide range of quality, and origin is not a guarantee of quality. For sapphire, Jammu and Kashmir receives the highest premium, although Burma, Sri Lanka, and Madagascar also produce large quantities of fine quality gems. The cost of natural sapphires varies depending on their color, clarity, size, cut, and overall quality. Sapphires that are completely untreated are worth far more than those that have been treated. Geographical origin also has a major impact on price. For most gems of one carat or more, an independent report from a respected laboratory such as GIA, Lotus Gemology, or SSEF, is often required by buyers before they will make a purchase. Colors Sapphires in colors other than blue are called "fancy" sapphires. "Parti sapphire" is used for multicolor stones with zoning of different colors (hues), but not different shades. Fancy sapphires are found in yellow, orange, green, brown, purple, violet, and practically any other hue. Blue sapphire Gemstone color can be described in terms of hue, saturation, and tone. Hue is commonly understood as the "color" of the gemstone. Saturation refers to the vividness or brightness of the hue, and tone is the lightness to darkness of the hue.: 333–401  Blue sapphire exists in various mixtures of its primary (blue) and secondary hues, various tonal levels (shades) and at various levels of saturation (vividness). Blue sapphires are evaluated based upon the purity of their blue hue. Violet and green are the most common secondary hues found in blue sapphires.: 333–401  The highest prices are paid for gems that are pure blue and of vivid saturation. Gems that are of lower saturation, or are too dark or too light in tone are of less value. However, color preferences are a personal taste, like a flavor of ice cream.: 333–401  The 423-carat (84.6 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. The 422.66-ct Siren of Serendip in the Houston Museum of Natural Science is another stunning example of a Sri Lankan sapphire on public display. Parti sapphires Particolored sapphires (or bi-color sapphires) are those stones that exhibit two or more colors within a single stone. The desirability of particolored or bi-color sapphires is usually judged based on the zoning or location of their colors, the colors' saturation, and the contrast of their colors. Australia is the largest source of particolored sapphires; they are not commonly used in mainstream jewelry and remain relatively unknown. Particolored sapphires cannot be created synthetically and only occur naturally. Pink sapphires Pink sapphires occur in shades from light to dark pink, and deepen in color as the quantity of chromium increases. The deeper the pink color, the higher their monetary value. In the United States, a minimum color saturation must be met to be called a ruby, otherwise the stone is referred to as a pink sapphire. Padparadscha Padparadscha is a delicate, light to medium toned, pink-orange to orange-pink hued corundum, originally found in Sri Lanka, but also found in deposits in Vietnam and parts of East Africa. Padparadscha sapphires are rare; the rarest of all is the totally natural variety, with no sign of artificial treatment. The name is derived from the Sanskrit padma ranga (padma = lotus; ranga = color), a color akin to the lotus flower (Nelumbo nucifera). Among the fancy (non-blue) sapphires, natural padparadscha fetch the highest prices. Since 2001, more sapphires of this color have appeared on the market as a result of artificial lattice diffusion of beryllium. Star sapphire A star sapphire is a type of sapphire that exhibits a star-like phenomenon known as asterism; red stones are known as "star rubies". Star sapphires contain intersecting needle-like inclusions following the underlying crystal structure that causes the appearance of a six-rayed "star"-shaped pattern when viewed with a single overhead light source. The inclusion is often the mineral rutile, a mineral composed primarily of titanium dioxide. The stones are cut en cabochon, typically with the center of the star near the top of the dome. Occasionally, twelve-rayed stars are found, typically because two different sets of inclusions are found within the same stone, such as a combination of fine needles of rutile with small platelets of hematite; the first results in a whitish star and the second results in a golden-colored star.... Discover the Sapphire popular books. Find the top 100 most popular Sapphire books.