Zirkel Mesa, 2012
Zirkel Mesa, Leucite Hills Mining District, Sweetwater County, Wyoming, USA
“Wyomingite (Pleistocene, 950-960 ka; Zirkel Mesa, Leucite Hills, Wyoming, USA)
Southwestern Wyoming's Leucite Hills are a group of Pliocene to Pleistocene volcanic centers that erupted lamproite lavas, a rare extrusive igneous lithology. Based on chemistry and mineral content, the Leucite Hills lamproite lavas have been categorized as ...
© James St. John