Rubies

A Ruby is a pink to blood-red Gemstone, a variety of the mineral corundum (aluminium oxide). The red color is caused mainly by the presence of the element chromium. Its name comes from Ruber, Latin for red.

The ruby is considered one of the four Precious Stones, together with the sapphire, the Emerald, and the diamond.

Prices of rubies are primarily determined by color. The brightest and most valuable "red" called pigeon blood-red, commands a huge premium over other rubies of similar quality.

After color follows clarity, similar to diamonds, a clear stone will command a premium, but a ruby without any needle-like rutile inclusions may indicate that the stone has been treated. Cut and carat also determine the price.

Rubies are a very hard gemstone, second only to Diamonds in most commonly known gems.

All natural rubies have imperfections in them, including color impurities and inclusions of rutile needles known as "silk". Gemologists use these needle inclusions found in natural rubies to distinguish them from synthetic or substitute Rubies.

Almost all rubies today are treated in some form, with heat treatment being the most common practice. However, rubies that are completely untreated but still of excellent quality command a large premium.

Historically, Myanmar or Burma as it was formally known, has always produced the best and most naturally abundant Rubies. They are also found in such places as Thailand, Cambodia, and in Afghanistan. More recently, large ruby deposits have been found under the receding ice shelf of Greenland.

Here in the USA, a few rubies have been found in Montana, North and South Carolina.

As with Diamonds and Emeralds, Rubies can graded using criteria that have become known as the four Cs, namely color, cut, clarity and carat weight. Geographic origin for Rubies is also a factor when it comes to value.

In the evaluation of colored Gemstones, color is the single most important factor. In nature there are rarely pure hues so when speaking of the hue of a gemstone we speak of primary and secondary and sometimes tertiary hues. In ruby the primary hue must be red. Any other color in a corundum gemstone causes it to be labeled a Sapphire.

The Smithsonian's National Museum of Natural History in Washington DC, has in it's collection, one of the world's largest and finest Ruby Gemstones. The 23.1 carats Burmese Ruby, set in a platinum ring with diamonds (see picture above), was donated by businessman and philanthropist Peter Buck in memory of his wife.