Precious Stone


The Ruby gets its name from its red colour (Latin: ruber). It was not until about 1800 that the ruby and the sapphire were recognised as belonging to the corundum species. Before then, the red spinel and the red garnet were also designated as ruby.

The ruby is a pink to blood-red coloured gemstone, a variety of the mineral corundum (aluminium oxide). The red colour is caused mainly by the presence of the element chromium. Any other variety of gem-quality corundum are called sapphires. The ruby is considered to be one of the four precious stones, along with the sapphire, the emerald, and the diamond.

Prices of rubies are primarily determined by their colour. The brightest and most valuable "red" called pigeon blood-red, commands a huge premium over other rubies of similar quality. After colour 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 (weight) also determine the price.


The Mogok Valley in Upper Myanmar (Burma) was for centuries the world's main source for rubies. It has produced some of the finest rubies ever mined, but in recent years very few good rubies have been found there. The very best colour in Myanmar rubies is sometimes described as "pigeon's blood red." In central Myanmar, the area of Mong Hsu began producing rubies during the 1990s and rapidly became the world's main ruby mining area. The most recently found ruby deposit in Myanmar is in Namya (Namyazeik) located in the northern state of Kachin.

Rubies have historically been mined in Thailand, the Pailin and Samlout District of Cambodia, Afghanistan and in Pakistan. Rubies have rarely been found in Sri Lanka, where pink sapphires are more common. After the Second World War ruby deposits were found in Tanzania, Madagascar, Vietnam, Nepal, Tajikistan and Pakistan. A few rubies have been found in the U.S. states of Montana, North Carolina, and South Carolina. More recently, large ruby deposits have been found under the receding ice shelf of Greenland. In 2002 rubies were found in the Waseges River area of Kenya.

There are reports of a large deposit of rubies found in 2009 in Mozambique, in Nanhumbir in the Cabo Delgado district of Montepuez.

Famous Rubies

Ruby is one of the most expensive gems, large rubies being rarer than comparable diamonds. The largest ever ruby that could be cut weighed 400.00ct; it was found in Burma and divided into three parts. Famous stones of exceptional beauty are the Edwardes Ruby (167.00ct) in the British Museum of Natural History in London, the Rosser Reeves star Ruby (138.70ct) in the Smithsonian Institution in Washington, D.C., the De Lang Star Ruby (100.00ct) in the American Museum of Natural History in New York, and the Peace Ruby (43.00ct) found in 1919 at the end of World War I.

Many rubies comprise important parts of royal insignia and other famous jewellery. The Bohemian St. Wenzel’s crown (Prague) for instance, holds a non-faceted ruby of about 250.00ct. But some gems, thought to be rubies, have been revealed as spinels, such as the “Black Prince’s Ruby” in the English State crown and the “Timur Ruby” found in a necklace among the English crown jewels. The drop-shaped spinels in the crown of the Wittelsbachs dating from 1830 were also originally thought to be rubies.