Of all the colored gemstones, ruby has consistently been at the top of the price-list. In 2015, a 25.59 carat Burmese ruby (the “Sunrise Ruby”), set in a ring by Cartier, was auctioned by Sotheby’s for $30.42 million. This was a world record price for a colored gemstone. It is no accident that the Sanskrit word for ruby (ratnaraj) translates to “king of gems”.
The word ruby comes from the classical Latin rubeus or ruber, both of which can be translated as “red”. Another early word for ruby is carbuncle, defined by the Oxford English Dictionary as “a large precious stone of a red or fiery color… (also) a mythical gem said to give out light in the dark.”
Ruby is a variety of corundum, a mineral that also produces sapphires. Pure corundum is colorless; trace amounts of chromium cause the red coloration of rubies. An increased level of chromium results in a deeper red color. With a specific gravity of 4.0, ruby is a fairly dense gemstone. Ruby has a hardness that is second only to diamond.
The deep red color of rubies is closely associated with blood, which mirrors life and vitality. According to the Gemological Institute of America (GIA), “Descriptions have compared ruby to the “blood from the right ventricle” or the first two drops of blood from a freshly killed pigeon. Historically, the term “pigeon’s blood” described the red to slightly purplish or pinkish red color of rubies with a soft, glowing, red fluorescence.” Pigeon’s blood is the most desirable color of ruby, and the Sunrise Ruby (which has pigeon’s blood coloration) has been aptly described by Swiss Gemological Institute as “a unique treasure of nature”.
The GIA states that color is the single most important factor in determining the value of a ruby. There must be a balance between darkness and lightness of color in any ruby. If the stone is too dark, the brightness will be affected; if the color is too light, the stone will be categorized as a pink sapphire, rather than a ruby.
Clarity is also very important, as inclusions can adversely affect the value of a ruby.
Rubies are often cut with a mixture of brilliant cuts and step cuts.
The GIA notes that “fine-quality rubies over 1 carat are very rare.” Commercial-quality stones can be found in much larger sizes.
Historically, the best rubies have been mined at the Mogok Valley, in Burma (present-day Myanmar). Other sources include Afghanistan, Greenland, Kenya, Madagascar, Malawi, Mozambique, Nepal, Pakistan, Sri Lanka, Tajikistan, Tanzania, Thailand, and Vietnam.
Ruby is the gemstone associated with the fortieth wedding anniversary, and it is also the birthstone for July.
[Photo courtesy of Sotheby’s]
Copyright © - Carla Bijouterie Gallery of Fine Jewelry