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Modesto Leonardi

Modesto Louis "Mo" Leonardi was born in Borgotaro, Italy on May 20, 1914, the son of Louis and Louise Leonardi; they move to the U.S. in 1921 and settled in San Rafael, California. Mo worked his way through college at the University of Nevada's Mackay School of Mines where he studied under Vincent Gianella, graduating with a B.S. degre in 1939 and a degree in Mining Engineering in 1954. He later served as Vice President of the Mackay School of Mines Alumni Association.

Mo worked for 31 years as Manager of Plant Production for the American Potash and Chemical Corporation in Trona, on the edge of Searles Lake, California. He lived in Tehachapi from at least 1993 until his death in 2001, so labels with that address ("Leonardi Associates") are the most recent.

He was a life-long mineral collector, very service-oriented, and enjoyed working with children and youth groups. He was responsible for creating the Trona Gem and Mineral Show, and for getting the company to open up a few wells each year for the people who would come to the gem and mineral show. They would drill some large bore holes down deep in the crystallized salt, into the brine-saturated layers of the lake, drop a little explosive down in the holes and use an air lift to hoist the crystals to the surface. Thousands of pounds of crystals of hanksite, halite, borax, sulfohalite etc. were and still are collected there each year.

After he retired he worked for the Parsons Company and spent a couple of years in Iran to help develop into production the giant copper mine in Sarchesma. The Shah was deposed before they could put it into production. Modesto Leonardi died on Decembber 7, 2001. His wife Lois (nee Lois C. Knight, married 1960) asked Rock Currier to appraise his collection, which Rock did (he was paid in specimens instead of cash), and it was then donated to the Mackay School of Mines.

Rock Currier (2007) Personal communication.
U.S. Federal Census 1930
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WILSON, Wendell E. (2019)
Mineralogical Record
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(1993 or earlier to 2001)
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