Spry Mining District, Garfield County, Utah, USAi

Regional Level Types
Spry Mining District	Mining District
Garfield County	County
Utah	State
USA	Country

The Spry mining district lies about 17 mi north of Panguitch on the Markagunt Plateau in northwesternmost Garfield County. The district covers a small, poorly documented, but diverse array of unimportant Hg, Mn, Ag, F, U, and clay prospects that have no recorded production. The Veater Hg prospect may be the oldest, discovered in 1915, and most interesting occurrence in the district (Doelling, 1975).
The Spry district lies on the Markagunt Plateau in the transition zone from the Basin and Range Province on the west to the Colorado Plateau on the east. The Spry district is associated with the Oligocene Spry intrusive (about 25 Ma). This concordant, subvolcanic intrusive has two separate intrusions, a larger southeastern body of 9 sq mi and a smaller northwestern body of 3 sq mi. The intrusive is a light-gray, fine-grained, porphyritic, calc-alkaline monzonite. Phenocrysts are plagioclase, orthoclase, and subequal biotite and hornblende. The Spry intrusive domed the Paleocene-Eocene Claron Formation and erupted to form the Buckskin Breccia and volcanic rocks of Bull Rush Creek. The Spry monzonite porphyry is cut by prominent N. 80 E.- trending vertical joints. The Spry intrusives have been described as two stocks but are currently believed to be two laccoliths (Doelling, 1975; Rowley and others, 2005).
Mineralization in the Spry district is primarily associated with the northwestern sides of the two bodies of the Spry monzonite porphyry. The Veater Hg prospect is on the northern margin of the northwestern laccolith. Mercury mineralization occurs along a northeast-trending normal fault with an unknown limestone in the footwall and andesite in the hanging wall. The recognized Hg minerals are cinnabar and metacinnabar in a 15- to 50-ft-wide zone of argillization and opalization with Fe-oxide staining, suggestive of a hot-springs Hg environment (USGS Model 27a). Five samples yielded 400 to 3000 ppm Hg with an average of 1340 ppm (Doelling, 1975). Half a mile to the southwest along this contact is a small Ag quartz vein with a sample reporting 69 ppm Ag. Farther southwest is a small fluorite vein (USGS Model 26 B) in the monzonite porphyry. Mineralization associated with the southeastern lobe of the Spry monzonite porphyry includes a couple of very small Mn prospects with psilomelane and pyrolusite and a U-clay prospect with uranophane and kaolinite (Doelling, 1975).