Stones Used In Indian Jewelry
STONES USED IN INDIAN JEWELRY
Coral is a calcium carbonate combined with magnesium. It is created by colonies of the marine coral polyp. Originally, the best red coral came from the Mediterranean, but pollution and over harvesting has greatly reduced that source. Today most top quality intense red coral comes from the Sea of Japan. It is sometimes referred to as "Mora coral". Generally, the deeper the color the higher the value, but this must be tempered by the presence, if any, of impurities, holes, fissures, etc. Also, the pink colored delicate"angel skin" coral and a creamy orange shade of coral have been popular and the highest grades of these are also expensive.
The highest grades of "ox blood" (intense red) coral can easily be $80 per carat and higher for the more rare large pieces. Coral should never be subjected to liquid cleaning solvents, nor extreme heat. It can turn white.
Sugilite is an alkali of iron, aluminum, manganese, lithium and water. It ranges from a yellow-brown in Japan to a beautiful deep purple from the Kalahari Desert in southern Africa. It is this latter that is used in jewelry. Sugilite has been registered as trade names: Royal Azul and Royal Lavulite. This stone ranges from an attractive light purple with deeper purple inclusions to a gem grade that can best be described as solid "grape jelly". Values range from a few dollars for the lighter shades to $80 a carat for the stones with the deepest and purest color. Also, like coral, larger cabachons of the highest grade are quite scarce and prices for these are even higher.
Please note: sugilite can be confused with the very beautiful, and also purple, spiney oyster shell (Spondylous princips). A magnifying glass will reveal "lines" in the spiney oyster shell specimen. Also, a scratch test with a needle or sharp knife will easily be seen on spiney oyster shell, but not on sugilite. Suglilite can also be confused with charoite, which is discussed below.
This popular purple stone is only found near the Chara River in Eastern Siberia. It is a calcium potassium silicate found with deposits of tinaksite (orange), augite (black) and feldspar (white). The range of color is extensive. When prepared in jewelry-ready cabachons, a deep "glittering" crystalline effect is noticeable. This stone is quite lovely in all it's manifestations, but becomes more valuable as the deeper purple intensifies and becomes increasingly dominant in the cabachon. The stone was first discovered and considered for jewelry use in 1976. It is still rather inexpensive, ranging from $2 to $4 a carat up to $20 a carat for the deeper colors. This too will change as more jewelers begin to see its beauty. In this regard, Indian silversmiths, such as Bruce Hodgins, are taking a leading role.
Gaspeite is a light, very soft and pleasing green stone that is a nickel carbonate colored by iron and magnesium. It is found on the Gaspe' Peninsula in Canada, hence the name. Most, however, is mined as a bi-product of nickel mines in western Australia. Gaspeite is similar in hue to Pixie and Damale turquoise and a recent shade of green from the Carico Lake turquoise mine in Lander County, Nevada. Also, some shades of varasite are quite similar to gaspeite. The stone is used as a cabachon in jewelry and as attractive color accents in silver and gold inlay and channel inlay. It's value is, at the moment, fairly uniform at about $5 to $8 a carat. This will undoubtedly increase. The gaspeite used in jewelry so far is a very pure light green, completely free of any matrix pattern or inclusions. The stones that are similar (see above) are nearly always seen with matrix.