Red-hot rubies

A look at one of the world's most coveted gemstones, the ruby

by

Editor

19 November 2012

Ruby is the king of the mineral Corundum, with a hardness index of nine, which ranks second only to diamond. Corundum has many different colours, with blue being sapphire, and red being ruby, the colour of which can be attributed to the presence of chromium. Ruby’s production is only a fifth of sapphire’s and it is the most precious coloured gemstone. The word ruby comes from ‘rubeus’ in Latin, which means red. It has been categorized as a corundum gemstone since the 1800s, when spinal and garnet were also generalized as ‘ruby.’

The crystalline structure of ruby is relatively small compared to other precious gemstones. Five carats are hard to find, and 10 carats or above are an invaluable rarity. Burmese ruby is best known in the market today for its characteristic red which seems to have a natural fluorescent glow. Countries such as Vietnam, Sri Lanka, Turkey, Brazil and Afghanistan also produce ruby. In Burma, ruby mining has over 1,000 years of history, and in northern Burma, the Mogok region has been producing some of the world’s most coveted rubies for the past 800 years. Due to overmining, Mogok rubies are more expensive than ever today, with prices that increase every year. In particular, five carats of premium gem quality can fetch a handsome price.

Ruby is valued not only for its rarity, but also for its colour. It can range from pink to blood red. Purplish or brownish tints are considered inferior quality. The most costly colour is Pigeon’s Blood, which is a pure red with a minute trace of blue. All natural Pigeon’s Blood rubies are sold at a premium: half of them come from Burma. When purchasing ruby, besides looking for a natural colour, it is important that the gemstone has not been artificially treated, as this can greatly affect its value. Nowadays, many rubies on the market have undergone heat treatment for improved gem quality.

One can understand the true value of a ruby by looking at its rarity, colour and naturalness. Besides these characteristics, a certificate issued by internationally recognized authorities such as the Gem Research Swisslab (GRS), Gübelin Gem Lab and Schweizerisches Gemmologisches Institut (SSEF) is your guarantee to investment-worthy ruby.