Actinolite

A splintery mass of dark green actinolite in tightly intergrown, contorted fibers, associated with dark brown andradite (lower right). The specimen bears several old labels, one of which reads “Actinolite- Purchase from Wards 1943?” Another gives the price as 75 cents, and the third, the number 262 in black ink on white paint, is that of Richard Hauck, in whose collection it once resided. It then passed to Steven Phillips upon his purchase of the Hauck collection, thence to Earl R. Verbeek (his specimen ERV-1744), and finally to the Franklin Mineral Museum (catalog no. FMM-2225). A label in the Phillips collection identified this specimen as tirodite, but on what basis is unknown. However, in a June 11, 1982 letter from Pete J. Dunn to his “Franklin Friends,” this specimen was shown to be actinolite on the basis of an electron microprobe analysis and calculations based on 23 oxygens in accordance with the IMA-approved nomenclature of Leake (1978).

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