Glass is made by combining sand (silica), soda (a form of salt), and lime (burnt limestone). When heated at very high temperatures, the materials melt together, forming common glass. By adding iron oxide (rust) the glass will turn a pale green, manganese oxide produces red, and cobalt in the melt turns the glass blue. Almost any color is possible, depending on the amount and combination of trace elements.
It was discovered that adding small amounts of lead produced a glass that was exceptionally hard, highly refractive and easier to cut. The amount of lead added along with cutting and grinding techniques used will determine how much sparkle and brilliance the crystal has. Even though lead is a known toxin, the wearing of crystal jewelry containing lead does not pose any health risks. Many fine crystals are available, but only one is known as “the diamond of the crystal industry.”
Daniel Swarovski was the son of a glass cutter who owned a small glass factory. Young Swarovski served an apprenticeship, becoming skilled in the art of glass-cutting and grinding. In 1892 he patented a hydroelectric cutting machine that allowed Swarovski to cut crystals with extreme precision and speed, producing the finest quality crystals available at an affordable price. Founded in 1895 to make use of Daniel Swarovski’s patents, the Swarovski Company has its own secret recipe for producing the world's finest crystal. While some components remain secret (and withheld from competitors) it is known that Swarovski Crystals are a man-made product of raw materials using natural minerals and pure quartz sand. The minerals and sand are combined and fired for an undisclosed period of time. Once removed from firing, they go through a very slow cooling process. The slow cooling process reduces flaws and imperfections in the final product. These specialty crystals have a lead content of 32% which enables them to be categorized as full lead crystal. To create crystal glass that lets light refract in a rainbow spectrum, Swarovski coats some of its products with special metallic chemical coatings. Aurora Borealis, or "AB", is one of the most popular coatings, and gives the surface a rainbow appearance. Other coatings are named by the company, Crystal Transmission, Volcano, Aurum, and Dorado. Coatings may be applied to only part of an object; others are coated twice, and thus are designated AB 2X, Dorado 2X etc.
In 2004 Swarovski released Xilion, a copyrighted cut designed to optimize the brilliance of Roses (components with flat backs) and Chatons (diamond cut). Swarovski has recently re-introduced Crystal Pearls to the marketplace. These simulated pearls each contain a crystal core and have a lustrous shimmer achieved by using a unique coating technology developed by Swarovski.