Virgin Valley opal district, Humboldt County, Nevada
By: by M.H. Staatz and H.L. Bauer, Jr
Contributors: Bauer, Herman L. (Herman Louis), 1925-
Series: Geological Survey circular -- 142; Geological Survey circular -- 142.
Publisher: [Interior Duplicating Section]
Published: 1951
Place of publication: Washington]
Language: eng
Subjects: Opals; Uranium
Notes: Cover title.