By Dr Emrys Chew

Ruby has been the world’s most valuable gemstone for thousands of years. Legends and stories abound about the nature and properties of ruby, and there are references to this gemstone in sacred and secular texts from around the globe. In Sanskrit, ruby is hailed as ratnaraj (‘king of gems’) or ratnanayaka (‘leader of gems’). In the Hindu religion, it is considered the most powerful gem in the universe; according to Hindu writings, the ruby represented the sun, and ancient Hindus believed that offering a ruby to the god Krishna would secure rebirth as an emperor. According to Jewish tradition, ruby was said to be the most precious of the twelve stones God created when he created all things, and this ‘lord of gems’ adorned the breastplate of Yahweh’s high priest. Rubies are cited in the Bible as a standard of measuring what is truly precious in life. To Christians, rubies would later become symbolic of divine love, demonstrated in the passion and atoning blood of Christ. European rulers would adorn themselves with rubies in accordance with Christian tradition, for the stone symbolized the sacrifice of a sovereign who put himself at the service of his people.

Historically, prior to the establishment of precise scientific classification, the term ‘ruby’ was applied loosely to several red gemstones, including red spinel (‘balas ruby’) and red tourmaline (‘Siberian ruby’). The so-called Black Prince’s ruby, a 170-carat gem now set at the front of the British Imperial State Crown, is actually a large red spinel. But from the strictly scientific point of view, ruby is properly defined as the red variety of the mineral corundum, a crystalline form of aluminium oxide. Corundum is one of the most durable minerals that exist; it has a hardness of 9 on the Mohs scale and is also very tough. In its common form, it is even used as an abrasive. In its pure state, corundum is colourless; it is traces of various metallic elements incorporated during the formation of the crystal that impart colour. Virtually all colours of corundum are classified as sapphire; only red corundum, coloured chiefly by chromium, is known as ruby.

Unsurprisingly, the most important factor in the value of a ruby is colour. The top qualities are as red as one can imagine: a saturated, pure spectral hue without any overtones of brown or blue. In fact, the word ‘red’ is derived from the Latin for ruby (ruber), which in turn derives from similar words in Persian, Hebrew, and Sanskrit. The colour intensity of a fine ruby is like a glowing coal; the ancient Greeks, writers such as Theophrastus, used the term anthrax to describe this stone that glowed ‘flaming blood-red’ like burning embers. It was probably the most intensely coloured substance our ancestors ever saw, and it is no wonder they ascribed magical powers to these inextinguishable fires that burned perpetually.

The ruby owes much of its magical and talismanic significance to its fluorescent, blood-like colour. Rubies were worn by many people to keep them in good physical and mental health; including protection against bleeding, pain, poisons, plague and other natural calamities. The ancients believed that the gemstone’s red fluorescence would fade if its wearer were in danger or ill health, and that wearing a ruby on the left side enabled a person to live in peace with his or her enemies. For many of these reasons, rubies were often set in rings and royal jewellery, or presented as gifts and tributes to rulers. Some of the most exquisite examples are to be found among the jewel collections of Iran and India; the Mughals, in particular, were arguably the wealthiest and most knowledgeable royal collectors of gems and the jewelled arts. Occasionally, a ruby is found to contain a shimmering six-rayed star, a scientific phenomenon known as asterism, caused by intersecting needle-like inclusions called rutiles. The rare ‘star ruby’ was regarded by astrologers as a stone of the sun; for centuries, the early cultures of the Orient considered it a sign of good fortune. In ancient times, wise men were thought to carry star rubies with them wherever they travelled, believing the star to be a source of great wisdom: the six-pointed star was said to represent the virtues of faith, hope, and destiny.

Despite being mined in all parts of the world for centuries, ruby is a mineral of very limited distribution. During the course of his travels in the second half of the thirteenth century, Marco Polo encountered gem deposits in the Hindu Kush mountains of Badakshan in northern Afghanistan, where “beautiful and valuable rubies are mined, like silver, from deep in the mountains,” as well as Ceylon (modern-day Sri Lanka), where “wonderful rubies are to be found… finer than in any other part of the world”. Knowledge of ruby extraction from the gem gravels of Ceylon would be corroborated down the centuries by other Europeans. Nowadays, some of the biggest and most brilliant of fine gem rubies still originate in Sri Lanka, although they are usually found as a by-product of sapphire mining. One of these, the 138.72-carat Rosser Reeves ruby, is one of the world’s largest and finest star rubies. Rubies also occur at several localities in the provinces of Chanthaburi and Trat, Thailand, where they are found in gravels with sapphires and spinels; these are generally of dark colour, inclining to a deep brownish-red, owing to high concentrations of iron.

However, Burma (modern-day Myanmar) is probably the world’s most famous source of fine rubies. One mining district, in particular, has stood out: the Mogok Stone Tract of Upper Burma, located 120 kilometres north of Mandalay. Although historical records indicate that Mogok has been worked since at least 1597, when a Burmese king secured its ruby mines from the local Shan ruler, the mines themselves are older than recorded history: stone age and bronze age mining implements have been found in Mogok, and it is estimated that five-sixths of the world’s cumulative production of rubies originated here. Rubies from Mogok’s rich deposits often possess a pure crimson colour described as ‘pigeon’s-blood,’ although that term is more fanciful than an actual practical standard in the trade today. The region also produces intense pinkish-red rubies that are striking and extremely beautiful. Many of the rubies from Burma display strong phosphorescence when exposed to ultraviolet rays like those in sunlight, which layers on extra colour. Burma rubies have a reputation for retaining their sumptuous, vivid coloration under all lighting conditions. No wonder the ancient Burmese held that rubies could even be seen in the dark: according to one legend, a king in Burma owned rubies that glowed so brightly, they lit up the city at night.

The ruby mines of Burma were first publicised by European writers towards the end of the fifteenth century. There are more specific references by Portuguese travellers from the sixteenth century, but they are of little practical importance. More light is shed by the seventeenth-century French traveller and gem merchant, Jean-Baptiste Tavernier, but even his account of the mines and their produce derives from secondhand oral sources. Apparently, their reputation was not then very impressive, or Tavernier would probably have made an effort to visit them. As things stood, Tavernier called Burma “one of the poorest countries in the world” but for its rubies, and even then, they were “not so abundant as generally believed”. Their value did not exceed 100,000 ecus per annum, and the Frenchman found it profitable to carry rubies from Europe to Asia for sale.

Yet the most probable reason for Tavernier’s disappointment is that gem-quality stones have always been scarce. For centuries, the kings of Burma decreed that all larger stones found were crown property. Any person found concealing such gems not only had them confiscated but risked summary execution. Early accounts detailed incidents in which entire villages were massacred for smuggling these gems out of the country. Tavernier himself observed that it was thus “difficult to meet one of good quality, weighing 3 or 4 carats, because of strict injunctions against allowing the removal of any which the king had not seen; and he retains all the good ones which are found among them”. If a ruby exceeding five carats came to light, and was deemed to be perfect, “it is sold for whatever is asked for it”. Ironically, this oppressive policy led to mass desertions among the miners, and the diminishing supply of rubies eventually forced Burmese king Thibaw to lease mining rights to foreign firms. Thibaw’s arbitrary revocation of the Bombay-Burmah Trading Corporation’s lease on the ruby mines in 1882 became a pretext for full-blown military invasion by the British. And yet, even after the British annexed Upper Burma in 1886, leasing the mines to a British firm that organised Burma Ruby Mines Ltd and then introducing modern mining technology and Western capital into the venture, profitability remained sporadic at best. Burma Ruby Mines worked the area until the early 1930s, when Mogok reverted back to indigenous mining and the traditional methods used for centuries before the arrival of the Europeans. Following the nationalisation of gem mining industries in Burma over recent decades, few foreigners have been allowed to visit Mogok and supplies of Burmese rubies have dwindled further. Perhaps more than ever, fine rubies in sizes above five carats prove to be exceptionally rare; and large, vivid red rubies remain more valuable than diamonds of the same size and quality. They can be priceless even in their rough form. In 1978, a 196.1-carat uncut Burmese gem was donated to the Natural History Museum of Los Angeles; the Hixon ruby is considered to be one of the most perfect large ruby crystals in the world. Then, in 1988, a magnificent 15.97-carat faceted Burma ruby was sold at auction; at $3,630,000, this was the highest price per carat of any coloured gemstone in history.

Further Reading

  1. Marco Polo, The Travels of Marco Polo, trans. Teresa Waugh (London, 1984).
  2. Jean-Baptiste Tavernier, Travels in India, trans. V. Ball, 2 vols. (Oxford, 1925), originally published in 1681 as part of his larger text, Les six voyages de J.-B. Tavernier.
  3. Christopher Cavey, Gems and Jewels: Fact and Fable (London, 1992).
  4. Peter Keller, Gemstones and their origins (New York, 1990).
  5. Patrick Voillot, Diamonds and Precious Stones (London, 1998).