JADE

Description: Jade refers to a green compact translucent rock, which consists either jadeite or actinolite. Jade formed from actinolite is termed nephrite jade. Beginning in the late 1950's attempts were made to market or promote a fine-grained actinolite-rich metavolcanic rock collected from the Little Rib River area near Little Chicago in Marathon County as a nephrite jade. G. N. Hanson, state geologist at the time of the discovery was sent several specimens. He was skeptical of its economic value, describing the material as "opaque, somewhat brittle and the only hint of green is rather drab olive patches". The rock also contained minor zoisite. (Wis. Geol. Nat. Hist. Survey files). A debate occurred between the marketers and the Wisconsin Geological and Natural History Survey as to whether or not the material was really accurately called jade. As the definition of nephrite jade is somewhat subjective, no conclusion was reached. The material is fine-grained actinolite, is green and does cut and polish. Wilson (1958) reports tumbling the material as well as making attractive rings and cabochons from it. He reports that the jewelry shows a "great many delightful patterns". He describes the material as follows: " Although most of it is opaque green, some has a bluish cast. Mottled and veined greens and blacks, greens and whites, some with yellow and yellowish patches, as well as solid greens occur. I have found one small brown piece." (Wilson, 1958). The few pieces the author has seen seem of poor quality compared to jade produced and marketed elsewhere. Is it really jade and of semi-precious quality? Beauty and value is in the eye of the beholder.

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