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William Yost

William H[enry?]. Yost III was born in Philadelphia, Pennsylvania on April 4, 1913, the son of Kathryn Flinn and William H. Yost, a carpenter. Bill married ____ Ledger in Philadelphia in 1939.

Micromounters Hall of Fames notes:

When Bill Yost started collecting minerals in 1928 (at the age of 15), he began a fascination with all phases of microscopical study, including the collection and preparation of diatoms. Despite early mechanical ability, he studied pharmacy and passed the Pennsylvania State Pharmacy Board in 1933. His mechanical abilities asserted themselves, and he worked in the aircraft industry and later, on prototype metals for electronic hardware, retiring as manager of an internationally important machine shop. In 1950 he developed the mineral specimen trimmer now in world-wide use.

Bill was a member of the Mineralogical Society of America, the Mineralogical Society of Pennsylvania, and Smithsonian Associates and was a participant in the Baltimore Micromount Symposia since their inception. In 1931, at the age of 18, he was elected a Junior Member of the Academy of Natural Sciences of Philadelphia, and went on to become part of the famous Philadelphia group of Micromounters which included Phil Evanoff, A. Schwabl, and Micromounters Hall of Fame members Paul Seel and Bill Hunt. Bill Yost himself was inducted into the Micromounters Hall of Fame in 1992. This group is credited with many innovations applicable to micromounting.

Bill was a charter subscriber to the Mineralogical Record in 1970. He presented an educational working exhibit of micromounting at many mineral shows, displaying the preparation of micromounts and the tools of the art. He has long felt that it was his mission to instill interest in the hobby by sharing duplicate micromounts and unmounted specimens with everyone interested. A leader in micromounting, and modest to a fault, he accumulated over 8,000 micromounts representing over 1,000 species.

He died in Philadelphia on March 3, 1999.

Social Security Death Index.
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WILSON, Wendell E. (2019)
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