May 6, 2019 TGMS General Meeting
Doors will be open at 6:30 p.m. and the meeting will start at 7:00 p.m.
FOR: TGMS Members and open to the public!
GUEST SPEAKER: Les Presmyk and his wife of over 42 years, Paula, are Arizona natives and both graduated from the University of Arizona. Les started collecting at the age of 10 and just attended his 56th straight Tucson Show.
Les first joined the Tucson Gem & Mineral Society in 1970 when he started at the U of A. He is a past President of the Mineralogical Society of Arizona, past Chairman and current vice-chairman of the Flagg Mineral Foundation). Les is a founding member of the University of Arizona Mineral Museum Advisory Board, recently appointed to the advisory Board of the new Arizona Mining, Mineral and Natural Resource Museum and a member of the Tucson Show Committee for 33 years.
He has explored and collected in a number of localities in Arizona, Missouri and Mexico and provided engineering expertise at the San Francisco mine in Sonora, Mexico, the Brushy Creek mine in Missouri and the Red Cloud mine in Arizona. Les has written several articles and co-authored the recently published “Collecting Arizona”. He has spoken at numerous symposia and mineral clubs throughout Arizona and the United States.
LECTURE TITLE: "The Pioneer Mining District, Pinal County, Arizona - The Silver King” -- was originally discovered by four ranchers and farmers from Florence in 1875. Work began almost immediately and the first shipments went to San Francisco. The main shaft was sunk and a community built up around this mine, along with the mill that was located a few miles away along Queen Creek, near Picket Post Mountain. The mine was profitable for the next 7 or 8 years and the town was abandoned by 1890 or so.
Meanwhile, the Silver Queen claim, discovered in 1874 by the same group, also sunk a shaft but within 300 feet the silver mineralization turned to copper. Prior to 1910, this very high grade copper deposit was not economic. Boyce Thompson examined the property in 1910, bought it, renamed it the Magma Mine, and started development. By 1915, enough ore had been defined that a mill and a railroad were constructed, along with the sinking of two additional shafts. The Magma Mine continued as a significant producer of copper, gold and silver through 1984 and then from 1988 through 1994.
While the mine has been closed since 1994, a deep, mineralized porphyry was discovered in the 2000s and is estimated to contain 1 billion tons averaging between 1.5% and 2% copper. So far, Rio Tinto, in partnership with BHP, have spent over $400 million in sinking No. 10 shaft, starting to deepen No. 9 shaft, and begin development. The future looks bright, once again, for this historic mining district.
For more information, contact the TGMS office.