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Roger Weller, geology instructor                     

Michael Schweska
Physical Geology
Spring 2005

                                       September Birthstone-Sapphire

Sapphire is the official birthstone for the month of September as adopted by the American National Association of Jewelers in 1912. It is also one of the birth stones for the Zodiac signs of Pisces, Taurus, Virgo and Sagittarius. See the birthstone tables for additional references to this stone. Sapphire is given as a gem for the 5th, 23rd and 45th wedding anniversaries while a star sapphire is given on the 65th wedding anniversary. Sapphire is 9.0 on the Mohs scale of hardness, the second hardest natural mineral. Sapphires are mined in Thailand, Sri Lanka, Australia and Cambodia. The United States, Nigeria, Kenya, Tanzania, China and Madagascar also produce some Sapphires. The deposits in Montana produce a range of fancy colors, and deep blue sapphires come from one of the world's largest deposits at Yogo Gulch, where Sapphires are small in size but have a beautiful blue. Some of the most famous sources for Sapphires are Kashmir and Burma. The Kashmir Sapphire, which was discovered over 100 years ago, has a rich velvety color prized by professionals. Burma Sapphires, from the same region that produces excellent rubies, are also very fine. Unfortunately, today these two countries produce very small quantities of Sapphires. Most fine Sapphires on the market today come from Sri Lanka, which produces a wide range of beautiful blues from delicate sky blue colors to rich saturated hues. Kanchanaburi in Thailand and Pailin in Cambodia are renowned for deep blue sapphires. Two relatively new mining localities are showing promise: Madagascar, which has produced some exceptionally fine stones in small sizes but has no organized mining yet, and Tanzania, which has long produced sapphires in other colors but is starting to produce blue colors as well from a new deposit in the south. Sapphire Click here for a picture in natural form. Click here for more faceted and natural specimens.


Blue is by far the most popular color for Sapphires, but they can be almost any color, including yellow, green, white, colorless, pink, orange, brown, and purple. Padparadscha is the name for a rare orange-pink variety of Sapphire and has a higher value than blue Sapphires. Heating colorless and very pale blue Sapphires to high temperatures is done to give them an intense blue color. This treatment can also improve the clarity of the stones by removing tiny inclusions. A rare variety of Sapphire, known as color changing Sapphire, exhibits different colors in different light. A color change Sapphire is blue in natural light, and violet in artificial light. A similar effect is also seen in Alexandrite. Sapphire was first created synthetically in 1902 and is hard to distinguish from natural Sapphires except by gemologists. Lab grown Sapphires range in price and smaller stones are frequently used in less expensive jewelry. The name Corundum comes from the ancient Sanskrit "kuruvindam", while the name Sapphire comes from the Persian word "safir", meaning "beloved of Saturn", (or Greek sapphiros). It is noted in several texts that Sapphire was the Lapis Lazuli of the ancient world, probably because the stones both have the same intense blue coloring.


The formula for Sapphire is a variety of Corundum, Al2O3, Corundum-Aluminum Oxide. Sapphires with inclusions of tiny, rutile needles exhibit an optical property called asterism. This is the star shaped effect seen in Star Sapphires and is usually only seen in cabochon cuts. Star Sapphires usually have six ray stars, but twelve ray stars are also known. Rarely, when Sapphires are cut en cabochon, they can demonstrate a cat's eye effect. This effect displays a thin band of light down the center of the stone and is known as chatoyancy. Legends, Myths and Healing Properties:

SapphireSapphire, gem of the heavens, or the divine gemstone, has been cherished for thousands of years. The ancient Persians believed that the earth rested on a giant Sapphire and its reflection colored the sky. Sapphire symbolizes sincerity and faithfulness, and is an excellent choice for an engagement ring. When Prince Charles gave Princess Diana a Sapphire engagement ring, couples all over the world were inspired to revive this ancient tradition. Its powers include spiritual enlightenment and inner peace. Sapphire is believed to offer healing properties for rheumatism, colic, and mental illness. It is also considered an antidepressant and an aid to psychokinesis, telepathy, clairvoyance and astral projection.



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Smithsonian Institute 1998-2005 Bernardine Fine Art Jewelry. 1999-2004 Jewelry Central, JC Store.
2004 Amethyst Galleries, Inc. 1995-2005 Loretta Elaine's Gems for Friends.