Diamonds, Kimberlites, Lamproites and Related Rocks in the United State

Exploration & Mining Geology, Vol. 4, No. 3, 1995

W. DAN HAUSEL, Senior Economic Geologist, Wyoming State Geological Survey, Laramie, Wyoming 82071, U.S.A

Hundreds of diamonds have been found in the United States. The majority of the discoveries occurred during the 19th century as a by-product of placer gold mining. Most of these early diamond ?nds have no known source, and in many cases are situated in areas unfavorable for diamond exploration based on current models that require kimberlite or lamproite to be emplaced in a stable Archean craton or Proterozoic craton margin. Diamonds have also been recovered in situ from lamproite at Murfreesburo, Arkansas, from kimberlite in the Lake Ellen region of Michigan, and in several kimberlites in the Colorado–Wyoming State Line district. Unveri?ed reports also suggest that diamonds may have been recovered from other related intrusions at a number of localities in the United States.
Keywords: Metals, Diamonds, Kimberlites, Lamporites, United States.