An article by Lee Anderson
This article explores stones (other than turquoise) that are commonly used in Indian jewelry: coral, sugilite, charoite, and gaspeite. To learn more about turquoise, read Lee Anderson’s articles.
Coral
Created by colonies of the marine coral polyp, coral is a calcium carbonate combined with magnesium. 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, although this axiom must be tempered by the presence, if any, of impurities, holes, fissures, etc. Also, the pink-colored, delicate “angel skin” coral and creamy orange coral have become popular; the highest grades are also expensive.
The highest grades of “ox blood” (intense red) coral can easily be $80 per carat and higher for rarer, large pieces. Coral should never be subjected to liquid cleaning solvents or extreme heat. It can turn white.
Sugilite
An alkali of iron, aluminum, manganese, lithium, and water, sugilite ranges from a yellow-brown in Japan to a beautiful, deep purple in the Kalahari Desert of southern Africa. The African sugilite is used in jewelry. Sugilite has been registered under the 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 per carat 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.
Note that sugilite looks like the beautiful (and also purple) spiny oyster shell Spondylous princips. A magnifying glass will reveal “lines” in the spiny oyster shell specimen. Also, a scratch test with a needle or sharp knife will easily be seen on spiny oyster shell, but not on sugilite. Sugilite can also be confused with charoite, discussed below.
Charoite
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 its manifestations but becomes more valuable as the deeper purple intensifies. It also 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 to as much as $20 per 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
This light, very soft and pleasing, green stone 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 byproduct of nickel mines in western Australia. Gaspeite is similar in hue to Pixie and Damale turquoise and to 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, gold, and channel inlay. Its value is, at the moment, fairly uniform at about $5 to $8 a carat. This will undoubtedly increase.
References / Recommended Readings
John Adair, The Navajo and Pueblo Silversmiths, University of Oklahoma Press, 1944.
Margery Bedinger, Indian Silver, Navajo and Pueblo Jewelers, University of New Mexico Press, 1973
M.G. Brown, Blue Gold, The Turquoise Story, Main Street Press, Anaheim, CA, 1975.
Larry Frank, Indian Silver Jewelry of the Southwest, Schiffer Publishing Ltd., Westchester, Pennsylvania, 1990.
The International Turquoise Annuals, vol. I and II, 1975 and 1976 (only two published) Impart Pub, Reno, NV. Note in vol. I the article on pages 31–55 by D. Allen Penick, “Turquoise, the Mineral that’s an Accident.”
Carl Rosnek and Joseph Stacy, Skystone and Silver, Prentice Hall, Englewood Cliffs, New Jersey, 1976.
Joseph E. Poque, Ph.D, The Turquoise, A report to the National Academy of Science, vol. XII, Second and Third Memoir, 1915. Reprinted in 1974 by Rio Grande Press, Inc., Glorieta, NM. (This reprint includes a foreword and details on Southwestern turquoise mines by Rex Arrowsmith and an excellent reference list. )
Stuart A. Northrop, Turquoise and Spanish Mines in New Mexico, University of New Mexico, Press, 1975.
Stuart A. Northrop, David L. Newman, David H. Snow, Turquoise, reprinted by General Printing and Paper Co., Topeka, KS. A reprint from El Palacio, vol. 79, No. 1, 1973, Museum of New Mexico.