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Facts About Created Sapphire

A corundum is a mineral comprised of aluminum oxide (Al2O3). It is found in various types of rocks. A sapphire is a corundum in transparent crystal form and is the earth's second-hardest natural substance, with diamond being the first. While the most widely known color of sapphire is blue, sapphires come in variety of colors such as yellow, orange and purple. Unlike imitation sapphires that bear only cosmetic similarities to the natural stones, sapphires that are created or "grown" by artificial means in laboratories share almost identical physical and chemical properties with the natural specimen.

Contents and Diameter
- Lab-created sapphires are produced by artificially fusing aluminum oxide with titanium. Specimens of these sapphires are created in a wide range of lengths and widths, ranging from 2 to 40 inches; however, as of 2011, a created sapphire's maximum diameter is 11 inches.
Commercial Uses
- Created sapphires are widely known to be used in the jewelry industry and for ornamental purposes. However, due to their hardness, durability, tolerance to extreme temperatures and optical properties, created sapphires are also used in many other markets including semiconductor manufacturing, aerospace, optics, industrial equipment, energy and the military.
Creation
- The most common methods of creating sapphires are the Verneuil method, the Kyropoulos or HEM method, the Czochralski or CZ method, the Bagdasarov or horizontal directed crystallization method and the Stepanov or EFG method. While all of these methods use the same primary materials, they differ in how the production processes are rendered. Their created sapphires vary in production time, size and use.
Verneuil Method
- Verneuil was the first method of creating crystal. It was developed by Auguste Verneuil in 1902. The largest sapphire that can be produced by this method is four inches in diameter. The growth time of a 0.02-inch specimen is two hours. Verneuil sapphires are mainly used for jewelry and small bearings for mechanical applications such as in windows and watches.
Kyropoulos Method
- This method was created by Spyro Kyropoulos in 1926. Noted for their high optical quality, Kyropoulos sapphires are used for items such as endoscopes, lenses, blue LEDs and missile domes. They are usually grown six inches in diameter, with a 55-pound ingot taking up to 14 days to produce. This method is one of the only two that can produce specimens with an 11-inch diameter.
Czochralski Method
- The Czochralski technique was developed by Jan Czochralski in 1916. These sapphires are used for products that include lasers, infrared and ultraviolet windows, microwave output windows and sodium lamp tubes. Specimens are created up to six inches in diameter, with growth time of up to 10 weeks.
Bagdasarov Method
- The Bagdasarov method was created by K.S. Bagdasarov in 1964. Ingots are generally grown to 6.5 inches in diameter, at a rate of 0.39 inches per hour. These sapphires are widely used for blue LEDs. This method is one of the only two that can produce ingots with an 11-inch diameter.
Stepanov Method
- A.V. Stepanov developed this technique during the 1960s. Specimens are commonly produced with a 0.4 inch diameter. These sapphires are used in bar code scanners, scalpels, military armor and aerospace windows.

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