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Roger Weller, geology instructor            regional geology  planetary  gems

Jeremy (Mia) Longoria
Physical geology
Fall 2008

The Gemstone for Your Birthstone-Sapphire


    In ancient times, Sapphires were believed to possess mystical powers - Priests used these gems to help them decipher Oracles, kings wore sapphire to protect them from wicked thoughts and charm divine favor, the Greeks sanctified this gemstone and because of its divine blue color associated sapphire to their Sky God - Zeus, and more. The gem was regarded as a symbol of truth, candor and endurance. It was believed that if a disloyal lover or spouse wore a sapphire ring, the brilliance of Sapphire would dim. It is the second hardest mineral found on earth, next only to diamond, which is the hardest mineral known to mankind. It is because of this hardness that sapphires are associated with longevity and endurance. Sapphire is the birthstone for those born in September and astrological stone for Libra zodiac sign. Sapphire is anniversary gift for the 5th and the 45th wedding anniversary.










      The historical source of sapphire is Sri Lanka. In ancient times, people used to dig the ground hunting for Sapphires and even today Sri Lanka remains to be a popular source of fine sapphires. The particular pinkish orange sapphire, padparadscha, is found only in Sri Lanka. Another major source fine sapphire is Australia. The Australian gemstones are deep velvety blue and dark inky in appearance. The most beautiful and the most valuable blue sapphires were found in Kashmir in India. In 1880, there was a land slide which uncovered this treasure. The Kashmir sapphire has a pure, intense blue color with a very subtle violet undertone, refined by a fine, velvety shine. According to some specialists, the rich color of this sapphire does not change its hue in artificial light. But due to the tough terrain of the region, this source is not being explored further. The Burmese sapphire has a color close to the Kashmir sapphire, beautiful deep blue. Other sources of sapphire include countries like Madagascar, Burma, America, Thailand and Cambodia.

   From the gemstone mines to the hands of the buyer, sapphires go through an adventurous journey. In the mines sapphires of all shapes and sizes are found mixed with the gravel. Miners swirl water in the pebbly gravel in cane baskets or screens and pick these precious pieces from the mud. This is adventurous as no one knows what the next lot of mud contains. Sapphire mines like the ones in Montana offer mining for tourists and enthusiasts.

   From the mines, the crystal is taken for lapidary. The crystal is carefully cut into different parts optimizing the size of each piece for the best color and quality available. Once this is done, the best suited shape and cut for that particular piece is determined. The crystal is then shaped and
faceted accordingly. The facets are important as they help in reflection and refraction of the light from the inside of gem which gives the gemstone its luster. A skilled lapidist can transform a rough stone into an exquisite piece of jewel.









    The transparent or the
lighter hues of sapphire are most often faceted. In lighter hues it is important that the light that enters the gem should reflect back evenly across the face of the gemstone, making it vivacious and more lustrous. The darker gemstones look good in all shapes and cuts. Sapphires are most often cut in an oval shape or in a cushion shape - a rounded rectangle. Sapphires can be found in a variety of cuts and fancy shapes including triangles, squares, emerald cuts, marquises, pear shapes, baguette shapes, and cabochon cuts (dome shape). Some sapphires with an unusual kind of tiny needle-like inclusions can be cut in a cabochon shape to display a six-rayed white star on its surface. Star sapphires are very rare especially perfect symmetry stars on deep blue body color.

Sapphires are the non red variety of the mineral corundum with a hardness of 9 on Mohs scale. Corundum is the hardest of all minerals only next to diamond, which has a hardness of 10 on Mohs scale. Higher the level of hardness, better the chances of the gemstone's resistance to scratches and abrasion. Also, the chemical structure of sapphire makes it very tough, helping in resistance to breaking, chipping and cracking. The hardness of this gemstone combined with the toughness makes sapphire perfect for daily wear.

  Corundum consists of pure aluminum oxide. Trace amounts of impurities (other elements like iron, titanium and chromium) when present in the corundum structure, make this crystal appear in different shades like
blue, yellow, pink, purple, orange or green. Sapphire includes all gemstones of the corundum mineral family except the fully saturated red variety, which is instead known as ruby, and the pinkish-orange variety known as 'padparadscha' (Sinhalese word for lotus blossom) exclusive to Sri Lanka.

apphires, like diamonds, are usually not free of inclusions. But as compared to emerald and ruby, sapphires possess higher clarity values. Flawless sapphires are found rarely and are very valuable. When buying a sapphire, the most important thing to be considered is color. Color is the single most important factor in determining the value or preciousness of a sapphire. In case of a sapphire the color of is more important than its clarity. Sapphires are rarely clean and even very expensive stones can be slightly included. Subtle differences in color can make great variations in valuations of fine sapphires. Fine gemstones of good color and clarity are always rare and valuable. Highly saturated medium or medium dark tones are best. Sapphires which are too dark or too light are worth considerably less.

     Corundum is a tough mineral and can be used in any type or style of jewelry. Sapphire comes in a spectrum of colors of the rainbow which makes it even more wearable. Sapphires can range in color and quality from common and easily affordable, to good quality and relatively precious, to rare, highly expensive gems like the star sapphire. This quality makes sapphires good for all occasions and moods like every day wear jewelry, evening wear jewelry, engagement rings, right hand rings, or even collector's items. These gemstones look good in almost all cuts and shapes. There numerous ways this gem can be fashioned and presented is awesome. The immortal queen of hearts, Lady Diana, had a sapphire in her betrothal ring, which pretty much explains the fashion and passion associated with sapphire.

Sapphire gemstones and sapphire jewelry needs to be cleaned often to keep the luster and lure alive. A thorough, soft brush scrubbing with a commercial jewelry cleaner or mild liquid detergent and water is sufficient to care for your gemstone if done at intervals such as every third or fourth time you wear it.