Sapphires can be natural or man made in a wide range of colors that include almost all the shades except red. Even the natural ones come in a large variety. For centuries, the natural ones have been obtained by extraction and mining, but the technological developments over the years allow their manufacturing in labs for making jewelry.

Crystallized Aluminum Oxide

Sapphires are basically mineral deposits found in many different kinds of rocks. They mainly comprise of aluminum oxide. Occasionally, crystallized lumps of these gemstones, classified as corundum, are formed in the lithosphere, a layer of the earth’s crust, under tremendous heat and pressure.

Crystals of pure aluminum oxide are clear and translucent, but impurities like chrome, titanium and iron that seep during the process of crystallization add color to the stone. Depending on the kind of impurities present in the gemstone, a sapphire may acquire blue, pink, yellow, or orange color.

The impurities in stones of the best quality don’t affect their clarity or shine, though the quality and hence the price of the regular and not so pure stones is adversely affected by impurities.

Rubies

Although sapphires come in almost all the colors of spectrum, since generations it has been a tradition to refer to the red and pink crystallized aluminum oxide as rubies. Though the two are given a different name and have different color, the lone chemical difference between the two is the presence of chromium in rubies, giving them their red tinge. Otherwise, both are identical. The hardness of these stones is next to diamond, making their maintenance easier.

Lab-Created Sapphires

Simulating the geological conditions under which sapphires are naturally formed creates synthetic sapphires. Using blowtorch, aluminum is melted and oxidized as a crystal, or grown from a superheated solution of aluminum with a crystallized base for creation of sapphires in a lab. Quality control measures allow enhancing the quality of these gems, compared to the natural ones, but they’re not so valuable as the latter because of their rarity.

Geography

Apart from its being synthetic or the natural one, the area from which the natural one has been recovered also decides its price. Natural stones coming from Burma, Kashmir and Sri Lanka, if not subjected to heat treatment, are often sold at higher prices in the gemstone market. Stones from other parts like India and North America, are also reputed for offering mid- to high-quality stones.

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