A MINERALOGICAL STUDY OF THE CONSOLIDATED TUNGSTEN MINE SKARN, TULARE COUNTY, CALIFORNIA

Contact metamorphism of the metasedimentary Kings sequence was driven by the 163 Mya intrusion of a quartz monzonite pluton, interpreted as a plutonic root of the Middle Jurassic volcanic arc developed along the westernmost margin of the Sierra Nevada orogenic belt. The Consolidated Tungsten Mine is one of a series ore-bearing skarns found throughout the Sierra Nevada and was classified by Newberry (1980) as being a “reduced” skarn with retrograde overprint. Petrographic analyses and SEM data confirm that the calcsilicate mineral assemblages are dominated by variable but abundant garnet, epidote, pyroxene, wollastonite, tremolite, calcite, plagioclase, and quartz; lesser but widespread scheelite, fluorapatite, zircon, sphene, ilmenite, rutile, and graphite; and the sulfides pyrite, pyrrhotite and sphalerite. Of particular interest are unusual enrichments in barium (stabilizing the Ba-feldspar, hyalophane), cerium (stabilizing a Ce-monazite and an unidentified Ce-silicate), and titanium (stabilizing iron-free Ti-andradite garnet). Thermobarometry of the regional metamorphic assemblages suggests relatively low pressure and temperature conditions (e.g., andalusite and cordierite) within the Lake Kaweah pendant at a distance from the aureole. Further analytical work will be aimed at constraining the contact metamorphic conditions as well as identifying possible trace element sources.