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Ruby

The red variety of the mineral corundum, in its finest quality the most valuable of gemstones. Only medium to dark tones of red to slightly violet-red or very slightly orange-red are called ruby; light reds, purples, and other colors are properly called sapphires. In its pure form the mineral corundum, with composition Al₂O₃, is colorless. The rich red of fine-quality ruby is the result of the presence of a minute amount of chromic oxide. The chromium presence permits rubies to be used for lasers producing red light.

See also: Corundum; Sapphire.

The finest ruby is the transparent type with a medium tone and a high intensity of slightly violet-red, which has been likened to the color of pigeon's blood. Star rubies do not command comparable prices, but they, too, are in great demand. The ruby was among the first of the gemstones to be duplicated synthetically and the first to be used extensively in jewelry.

Material Notes:
Gem-Tone?GC-13P Ruby Red is a rich, strong blue shade red colorant intended for use in clarified polypropylene. Clean, haze free, non-warping color formulations can easily be achieved with the use of this colorant. No blooming or plateout problems will be seen with Gem-Tone?colorants. These materials can be incorporated into polyolefin resins at levels as low as 0.05% and can be increased to higher levels to achieve your desired effect.

Traditionally, India was considered to be the source of all rubies, as testified by an overwhelming collection of literature for over two thousand years. The highest quality rubies, the most transparent with the best color, are usually from Burma, and can actually be as valuable as diamonds, or even more so. The ruby is actually very closely related to the sapphire, both being part of the corundum family. They are both made of the same mineral, but are of course, different colors. The ruby is a little softer than the sapphire, which may seem strange as they are both made of the same mineral, however nature never makes each gem in a mineral family the same.

Next to diamonds, rubies are the hardest gems, with a 9 rating on the Mohs scale. Their hardness makes them ideal for jewelry of all kinds, because one does not have to be especially careful when wearing them. Since rubies are so hard and durable, they are easy to care for, however it is not recommended to wear a ruby if you are doing any sort of rough work or are using harsh chemicals. Rubies should be stored in a fabric-lined box, away from other pieces of jewelry, as they may scratch other, softer gemstones. When it is time to clean them, you can use soapy water and a brush, or a commercial jewelry cleanser. It is important to rinse the stone thoroughly and dry it, after cleaning it.

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