SAPPHIRE

By Dr Emrys Chew

Long cherished as the ‘celestial gemstone,’ sapphire has been treasured by human civilisation since at least 800 BCE. The ancient Persians believed that the earth rested on a giant sapphire and its reflection coloured the sky. While ‘sapphire’ stems from sappheiros, the Greek word for blue, the stone is actually found in all the colours of the heavens: from midnight blue to the bright blue of noon sky in the Mediterranean, golden sunrise to fiery reddish-orange sunsets, and the delicate violet of twilight. The most famous and highly prized sapphires are a rich, intense royal blue. According to the Hebrew scriptures, sapphire was one of the twelve stones adorning the breastplate of the Jewish high priest, a precious standard against which wisdom itself was to be measured, and a gem associated with the very throne of God. Because sapphires represent divine favour, justice and truth, they were the gemstone of choice for kings and clergy, the symbol of pure and wise rulers.

Sapphire is the name given to all colours of the mineral corundum (crystalline aluminium oxide) except red corundum, which is called ruby. Prior to the establishment of strict scientific classification, from ancient times up until the late nineteenth century, the name sapphire was more generally applied to several blue gemstones (including lapis lazuli) as well as the blue variety of corundum. All other gem varieties of corundum were given names corresponding to those stones that they closely resembled; hence, yellow sapphire was known as oriental topaz, green sapphire as oriental emerald or peridot, and purple sapphire as oriental amethyst. In 1902, however, mineralogist Count de Bournon pointed out that “the analogy existing between the stones known by the names corundum, sapphire, oriental ruby, oriental hyacinth, &c. is so strong and complete, as no longer to permit us to doubt that they ought all to be considered merely as varieties of the same substance, to which I have given the general name of corundum”. Henceforth, when the term ‘sapphire’ is used alone, it refers to blue corundum, coloured mainly by traces of iron and titanium. This may range from a very pale blue to deep indigo, the most valuable being a vivid, medium or medium-dark ‘cornflower-blue,’ devoid of green, gray or black overtones. All other colours of sapphire are known collectively as fancy sapphires, and use a colour prefix in their individual names. Much sapphire is, in fact, unevenly coloured; it is also dichroic, that is to say, the colour changes with the direction of view. Some varieties display a distinct colour change according to lighting conditions, from green to red or blue to mauve in daylight and incandescent light. One variety—the star sapphire—is found to display a shimmering six-ray (or more rarely, twelve-ray) star when viewed with a single bright light source; this is a scientific phenomenon known as asterism, caused by intersecting needle-like inclusions called rutiles. But whatever the colour or variety, sapphire is one of the most durable gemstones known to humankind. With a rating of 9 on Mohs’ scale, sapphire is harder than any other gem but diamond; and it is tougher, having no cleavage plane so that it cannot be cut with a single blow like a diamond.

Due to the richness and intensity of its coloration, coupled with excellent durability, sapphire has been revered for its spiritual and talismanic properties for centuries. Buddhists believe that a sapphire can stimulate the desire to pray and meditate. Since the Middle Ages, sapphires have also been worn by the bishops, cardinals and popes of the Roman Catholic Church. The church chose sapphire as the supreme symbol of the light of God, and its clergy were advised to wear a sapphire on the right hand as a token of the powers of heaven, grantor of their authority to administer blessings and judgments. Not only did the colour represent the heavens, the stone itself was thought to be sacred and to bestow on its wearer the virtues of being ‘pacific, amiable, pious and devout’. Saint Jerome wrote that the sapphire could calm a person’s enemies, the gemstone long being held as a powerful safeguard against sorcery, spells, poison, witchcraft and demons. At one time, by exuding its heavenly rays, the mere presence of a sapphire was supposed to kill any venomous creature that came close to the wearer. The stone was employed medicinally to treat eye inflammation, nosebleeds, ulcers, boils, swelling, depression, and heart problems. Even the seventeenth-century chemist Robert Boyle accepted its usage in the treatment of pain and disease. The star sapphire was regarded by many as the most potent of amulets; and the three arms of the star were interpreted as representing faith, hope and destiny. As late as the nineteenth century, the explorer Richard Burton carried a large star sapphire with him on his travels in Africa, ostensibly to overawe the indigenous communities that he encountered.

Sapphires are found in many parts of Asia, Africa, Australia and the Americas. While Australian sapphires today account for nearly 70 per cent of the world’s commercial production, Sri Lanka (formerly Ceylon) has produced historically more fine gem-quality sapphire than any other locality. Marco Polo (in the thirteenth century) and Jean-Baptiste Tavernier (in the seventeenth century) both acknowledged this fact during the course of their travels. In particular, the gem deposits of Ratnapura have yielded quantities of sapphire for over 2,000 years. Some of the treasures found in the crown jewels of Europe and museums of the West originated from this fabled ‘City of Gems’; these include the spectacular 104-carat Stuart sapphire (now part of the British crown jewels), the 98.6-carat Bismarck and 423-carat Logan sapphires, and the gray-blue 563.35-carat Star of India and deep purple 116.75-carat Midnight Star (all on display at the Smithsonian Institution). Ceylon sapphire ranges in hue from delicate sky blue to a rich saturated indigo. Occasionally, among the spectrum of other colours, intense pinkish-orange sapphires are also discovered; these, the most rare and prized of all the fancy sapphires, are called ‘padparadscha’ (deriving from the Sinhalese word for the lotus flower). One of Sri Lanka’s finest padparadschas, weighing some 100 carats, is on display at the American Museum of Natural History in New York.

In recent years, Montana in the United States, Kanchanaburi in Thailand, Pailin in Cambodia, and the island of Madagascar have also become renowned for gem-quality sapphires. Still, most gem historians conclude that the most famous sources are Kashmir and Burma (present-day Myanmar). Kashmir sapphire was first discovered in 1881 when a landslide in the northwestern Himalayas uncovered beautiful blue pebbles that were quickly brought to the attention of the local Maharajah. Connoisseurs prize the velvety, mist-like texture that enhances the richness of the magnificent cornflower-blue coloration; and unlike most other sapphires, Kashmir sapphires have a reputation for retaining this sumptuous hue whatever the lighting conditions. Burma sapphires, from the same Mogok region that yields fabulous rubies, are also exceptionally fine. Tending towards deeper shades of royal blue, the most valued stones are sometimes described as displaying flashes of electric ‘peacock-blue’. Nowadays, however, these two sources account for only a very small percentage of sapphire on the market. The high altitude and harsh climate restricted mining in Kashmir to at most two or three months a year, with the bulk of the mining taking place between 1882-87. More or less abandoned since 1937, the mines are now thought to be largely worked out. Consequently, the few Kashmir sapphires on the market tend to be found almost exclusively in antique jewellery and estate collections. Burmese stones are more widely available but still rare, due to prevailing political instability in the region. Some of the remarkable pieces emerging from Burma include the 330-carat Star of Asia and the 62.02-carat Rockefeller sapphire which, selling at auction in 2001 for $3,031,000, holds the per carat and total price world record for a single blue sapphire.

Further Reading

1. Count de Bournon, ‘Description of the corundum stone and its varieties’, Philosophical Transactions of the Royal Society of London, vol. 22, 1902, pp. 233-36.
2. Marco Polo, The Travels of Marco Polo, trans. Teresa Waugh (London, 1984).
3. 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.
4. Christopher Cavey, Gems and Jewels: Fact and Fable (London, 1992).
5. Patrick Voillot, Diamonds and Precious Stones (London, 1998).