Adamite and Austinite - Gold Hill Mine, Tooele County, Utah

Contributed by: Chris Clemens
Date: Apr 30th, 2026
Locality: Gold Hill Mine, Gold Hill, Gold Hill Mining District (Clifton Mining District), Tooele County, Utah, USA (See on Mindat)
Size: 55 x 42 x 67 mm
Weight: 84 g

Description:
Specimen consisting of white, radiating sprays of acicular crystals of austinite, and small, greenish yellow prismatic crystals of adamite on a rust-colored limonitic gossan matrix. Collected from the Gold Hill mine, Deep Creek Mountains, Tooele County, Utah. Under shortwave UV the austinite fluoresces white, and the adamite shows a classic green uranyl-activated response. The austinite (and possibly the adamite) also shows blue/white phosphorescence after shortwave UV. Both adamite and austinite are zinc arsenate minerals.

The closeup images show austinite as glassy, white to colorless, needle-like crystals, and adamite as smaller green/yellow prismatic crystals.

Shut down in 1945, the Gold Hill mine is a former producer of gold, silver, copper, arsenic, lead, zinc and barium, and is located in the Deep Creek Mountains of northwest Utah, approximately 10 miles east of the Nevada border. The last set of photographs show the Gold Hill Mine location.

Originally posted by Chris Clemens on Nature's Rainbows in 2017.