I'm pleased to offer this attractive Calcite with Pyrite and presumed Marcasite from the Sierrita mine, Green Valley, Pima County, Arizona. The specimen measures 2.87 x 1.95 x 1.54 inches or 7.30 x 4.96 x 3.91cm.

  This was recently donated to the Pinal Geology and Mineral Museum in Coolidge, Arizona by Ron Gibbs (rongibbsite) of Oro Valley, Arizona. The specimen is accompanied by Ron's signature label and mentions that the specimen was collected in 2011 by Kyle Johnson. I've been tasked with offering excess specimens, etc. from the museum here on eBay and your purchase will directly benefit the only geology museum in Pinal County!

  This piece shows lustrous calcite crystals with bright pyrite and microscopic duller clusters of presumed marcasite crystals. The calcite fluoresces a muted orange-red color under shortwave UV light. If your interest in this piece is mostly for its fluorescence, I would recommend against its purchase!

  The Sierrita mine first saw production in 1907 after being discovered in 1895. Stripping for open pit operations began in 1957 and the mine began open pit production in 1959 and has been a reliable producer of copper, molybdenum, and rhenium. It is currently owned and operated by Freeport McMoRan, Inc. of Phoenix.

  Azurite, chrysocolla, and malachite are the main oxide ore minerals while chalcopyrite and molybdenite are the primary sulfide ores and chalcocite is the main secondary sulfide ore.

   

  Please check my feedback and my other eBay items. All specimens are carefully wrapped, come with complete and accurate labels and are quickly shipped. As always, your complete satisfaction is unconditionally guaranteed and I even offer FREE return shipping on any item that fails to satisfy for any reason---you can't go wrong. I'm reminded of the firm pledge printed on the old Foote Mineral Company mineral catalogs from more than a century ago,  

  "Quality of specimens is assured as we permit return of specimens at our expense."

  

  Thanks for looking!

  I buy collections! Please contact me if you have a collection for sale or know of one that is available. I will pay a finder's fee to anyone that can point me to an eventual purchase!