California Division of Mines Speial Report 53 Igneous and Metamorphic Rocks of Parts of Sequoia and Kings Canyon National Parks, California

The area considered in the present report is principally in Sequoia National Park and is not open to prospecting or development of mineral resources. The portion of the area that is within Sequoia National Forest has been prospected to some extent, and the Redwood Canyon area, which was only recently incorporated into Kings Canyon National Park, has also been prospected.

The only mineralization found in the plutonic rocks by the writer consists of a minor occurrence each of molybdenite and copper carbonates. The extreme rarity of quartz veins precludes much fissure-vein type mineralization.

Tactite, locally scheelite-bearing, has been developed from the calcareous metamorphic rocks, particularly in Redwood Canyon and along the North Fork of the Kaweah River. The Barrington tungsten mine, on the North Fork of the Kaweah River, contains the only scheelite in other than trace amounts that was found in the area. The workings of the Barrington tungsten mine consist of two short adits 150 feet in total length. The scheelite is contained in a garnet-pyroxene-quartz tactite. The metamorphic body that contains the tactite is a large schist xenolith near a roof pendant. In 1944, a small tonnage of ore was shipped to the Metals Reserve Company (Krauskopf, 1953). The mine was idle in 1951.

The Redwood Canyon mine, described by Jenkins (1943), consists of a 40-foot shaft, a small adit, and several trenches in a layer of garnet tactite. The tactite was worked for tungsten and copper, but also reportedly contained small amounts of silver and gold. Specimens collected at the prospect by the writer contained only traces of scheelite, but did have sparse amounts of chalcopyrite and bornite; weathered surfaces showed considerable copper carbonate staining. The mine shipped a small tonnage of high-grade ore to the Metals Reserve Company in 1943-44 (Krauskopf, 1953).

Considering the extensive outcrops of marble within the mapped area, undiscovered tactite bodies may be present, particularly in the less accessible, brush-covered areas.