The gem of the month for June is Pearl – the only gemstone created by a living organism and long considered the most magical and feminine of gems.
Gemmology Matters: Pearls are organic gems formed within oysters or mollusks when a foreign substance (most often a parasite – not a grain of sand) invades the shell of the mollusk, entering the soft mantle tissue, and picking up epithelial cells. In response to the irritation, the epithelial cells form into a sac (known as a pearl sac) which secretes a crystalline substance called nacre, the same substance which makes up the interior of the oyster's shell, which builds up in layers around the irritant, forming the pearl.
In nature, only a very small percentage of oysters will ever produce a pearl at all. Of these, only a handful will develop to a desirable size, shape, and colour. It is often estimated that only one in ten thousand oysters will naturally produce a gem quality pearl. This rarity has led to the development of the cultured pearl industry arising from Japanese research in the early 20th Century. Today the cultured pearl industry has effectively replaced the natural pearl industry. Natural pearls are now collectors pieces commanding extremely high prices. Cultured pearls may be distinguished from natural pearls through the use of x-rays, which reveals the inner nucleus of the pearl. Western Australia has a valuable and successful pearling industry, worth around $200m annually, and is the world's top producer of prized silver-white South Sea pearls. Cultured saltwater pearls are produced in a number of other countries around the world with different species producing a range of colours specific to the location (eg. black pearls from Tahiti). Freshwater pearls are cultured in freshwater mussels, mostly in China. As pearls are quite soft and delicate, they should be treated with care and not exposed to chemicals or extremes or heat or dryness. Pearls are often treated to improve appearance – apart from the common treatment of bleaching/cleaning, treatments may include:
- Dyeing – silver nitrate used to darken the nacre, other dyes may create colour tints
- Irradiation – gamma radiation to darken the nucleus in akoya pearls and the nacre layers in freshwater
- Lustre Treatments – coating treatments on the surface of the pearl to artificially enhance lustre
Mythology and Lore: Pearls were highly valued in ancient times as they were so rare. As long ago as 2300 BC, Chinese records indicate that pearls were prized possessions of royalty. In Hindu culture, pearls were associated with the Moon and were symbols of love and purity – it is said that Krishna discovered the first pearl, which he presented to his daughter on her wedding day. The tradition for brides to wear pearls on their wedding day may have arisen from this ancient belief. Islamic tradition holds pearls in even higher regard. The Koran speaks of pearls as one of the great rewards found in Paradise, and the gem itself has become a symbol of perfection. Christianity also adopted the pearl as a symbol of purity. Pearls are also said to symbolize tears, to provide love and fertility, to symbolize purity, and to ward off evil.
Pearl is the Modern birthstone for June and is associated with the zodiac signs of Gemini and Cancer. Fresh water pearls are given on the 1st wedding anniversary. Pearls are also given on the 3rd, 12th and 30th anniversaries.
Alternatives in White: Nothing really has the lustre of a fine pearl. Rainbow Moonstone has a similar appearance with an opaque white colour featuring a shimmering adularescence. Some of the pale coloured opals may also have a similar glowing white colour. However, nothing compares to a strand of fine pearls – classic elegance that never goes out of style.
Links of Interest:
- Wikipedia article on Pearl
- Commercial Fisheries of Western Australia – Pearling
- Bernadine Fine Art Jewelry – article on Pearl
- Pearl-Guide.com – the worlds largest pearl information resource
Thats all for now from Aussie Sapphire