Quality Pearls on Sale!

Arizona -- Arizona is well known for its petrified wood because of the Petrified Forest National Park, and petrified wood ranks third in value of commercially produced gemstones. It is generally accepted that the Park contains the most colorful examples of silicified logs in the world.

Petrified wood occurs in every county in the State, but the commercial production is essentially from privately owned lands in Navajo and Apache Counties near the Petrified Forest. Federal regulations restrict collecting petrified wood on public lands to 250 pounds plus one piece per person per year, none of which is supposed to be sold commercially. The regulation essentially eliminates production from federal lands. Pieces as small as 1/4-inch to sections of logs 5 feet in diameter are recovered from the surface of the ground or with minimum excavations for use in the lapidary trade.

Arizona petrified wood has the broadest range of applications of any gem material produced in the State. The material is suitable for tumble polishing for use in baroque jewelry or for cutting into cabochons for jewelry and display. Freeform and calibrated slabs are polished for pen and pencil set bases and bases of other items, and polished slabs are used for clock faces. Additionally, large blocks, limb sections, and geometric shapes are used as bookends and decorator pieces. Objects of art, principally carvings, are produced, and furniture such as coffee and end tables are made from the petrified wood.

Arizona is the only State currently to have commercial production of fire agate. Fire agate is a form of chalcedony which contains inclusion of iron oxides that result in a play of colors much like that of precious opal. Eleven operations in Arizona report either commercial production of fire agate or dig-for-fee production. The material is produced in Graham, Greenlee, Maricopa, Mohave, and Yuma Counties.

Fire agate is cut into freeform and calibrated cabochons for use in the manufacture of silver and gold jewelry. The material is popular in the southwest and with hobbyist lapidaries throughout the United States. Fire agate also has been used and is currently used in Indian style jewelry.

California -- California's "Mojave Blue" agate has gained a great deal of attention in the past several years. This pastel blue or blue-gray agate cuts into attractive cabochons for jewelry and, in the hands of an expert carver, makes outstanding carvings.

Colorado and Utah -- These States have deposits of fine quality jasper, agate, petrified wood, and agatized dinosaur bone. These deposits are found over a large area of both States and on both sides of the continental divide in Colorado.

Florida--The famous silicified coral, first found in the Tampa Bay area around 1825 is the only gemstone of note from the State. Since its discovery in Tampa Bay, the agatized coral also has been found at Tarpon Springs, south of New Port Richey, near the town of Kathleen, and along the banks of the Suwanee River in Hamilton, Columbia, and Suwanee Counties. The material is found in two forms, as geodes, which represent partial replacement of coral, and as solid pieces which represent total replacement.

The coral is replaced by a waxy, translucent, botryoidal, varicolored chalcedony. The geodes are most often used as mineral specimens, but cabochon and tumbled gems can be made from the thin geode lining. The total replaced coral can be cut into attractive cabochons. The material can be blue, red, brown, amber, white, black, or a combination of these colors.

Idaho -- Jasper mining was beginning to make a comeback in the State, particularly with the operation of the Willow Creek jasper mine when in 1992, the untimely death of one of the partners mining the property, resulted in jasper mining reverting to hobbyist and professional collectors. Production of the various jaspers should be adequate to meet demand for the foreseeable future.

Montana -- Montana moss Agate is the grayish-white to gray translucent chalcedony containing dendrites. The black, brown, or red tree-like or scenic dendritic growths are actually included minerals of manganese and iron. Most of the moss agate is found as water worn cobbles in the Yellowstone River or its drainages between Billings and Sidney. The material can be collected in Yellowstone, Treasure, Rosebud, Custer, Prairie, Dawson, and Richland Counties. The agate has long been a favorite of hobbyist and professional cutters because of the beautiful and highly variable patterns, the durability, and ease in cutting and polishing.

New Mexico -- Varieties of agate, jasper, chert, or petrified wood are found in 15 of New Mexico's 32 counties. An area of about 100 hectares near Deming, New Mexico Rockhound State Park, is set aside for the non-commercial collecting of agate, jasper, and petrified wood.

Tune in next week for more states.

Article source: U.S.G. S.

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