Tibbetts Mine (Evening Star Mine), Duquesne (Washington Camp), Patagonia District, Patagonia Mts, Santa Cruz Co., Arizona, USA

‡Ref.: Schrader, F.C. & J.M. Hill (1915), Mineral deposits of the Santa Rita and Patagonia Mountains, Arizona, USGS Bull. 582: 344-345.

Arizona Bureau of Mines card file Santa Cruz County.

MRDS database Dep. ID file #10137582, MAS ID #0040230383.

A former underground Pb-Ag-Au-Cu mine located in the center N½SW¼ sec. 35, T23S, R16E, about 1/8 mile east of Washington, and the claim adjoins that of the Pocahontas on the north, on National Forest land. Owned and operated by M.M. Trickey and partners (Oliver and Trickey) of Washington (1943), This mine has been worked since 1884.

It is on the granite porphyry and limestone contact. Except for the local silification of the limestone and the occurrence of specularite, there is no indication that the deposits are contact metamorphic. The vein dips 80ºN.

A fault occurs at the face of the west drift, which is in limestone, that dips 80ºNW, with granite porphyry on the hanging wall side of the winze below the drift. Along this fault contact occurs from 3 to 6 inches of reddish, iron-stained gouge containing galena, a little malachite, and some specularite.

The east drift lies in a sheet of soft reddish gouge and breccia in which some pockets of galena and cerussite were found.

Mineral deposits of the Washington-Duquesne area occupy a limestone-sediment belt (2.5 miles long by 1.25 miles wide) surrounded by igneous rocks which also form detached masses and dikes within the belt.

Developed to a depth of 200 feet by tunnels and drifts, stopes, winzes, and raises, aggregating about 1,600 feet of work. The tunnel runs S.26ºE. into the hill a distance of 144 feet. The west drift runs S.75ºW. for 120 feet to a 15 foot inclined winze which descends to the north. The east drift is 63 feet long and bears N.60ºE., at the end of which is an irregular winze inclining eastward is sunk to a depth of 136 feet.