Thursday, August 25, 2016

Monday, June 20, 2016

Monday, August 10, 2015

Sunday, February 22, 2015

Saturday, March 15, 2014

Thursday, September 05, 2013

Copper




Copper sheet from the White Pine Mine, Keweenaw Peninsula, MI, USA on display at the National Museum of Natural History

Saturday, January 02, 2010