BIKITAITE FROM THE FOOTE MINE, CLEVELAND COUNTY, PIEDMONT OF SOUTHERN NORTH CAROLINA

Unusually large euhedral prismatic crystals (up to 2.8 cm long) and intergrown crystal aggregates (ICA) of bikitaite (Li2Al2Si4012.2H20) were discovered in an exposed nearly vertical yellow-orange plastic clay filled druse about one meter long, 10-12 cm wide and 0.8 m deep.

These crystals are larger than those from Bikita, Zimbabwe; the only other known occurrence. X-ray diffraction and optical properties are very similar to bikitaite from Zimbabwe.

Bikitaite crystallized in the tertiary stage (White, 1981). The clay contained many free crystal and small pegmatite fragments covered by subhedral albite. Bikitiate crystallized on the albite, (ICA) in the clay, the walls of the druse, suggesting late stage hydrothermal mineralization filling a breccia zone.

Located in the Kings Mountain Belt, just off Interstate 85 and Dixon School Road, a complex of metaigneous and metasedimentary rocks extends for at least 80 km from the Catawba River on the north to the area south of Gaffney, South Carolina. These rocks were subjected to several episodes of metamorphism and deformation, they are highly variable in mineralogy and texture; the most common rocks are: granite and hornblende gneiss, amphibolites, quartzite and mica and hornblende schist.

The amphibolites were intruded approximately 352 -+10 m.y.a., by a swarm of spodumene pegmatite dikes (Kish, 1977). A detailed description of the mine (Kesler,1961) shows that the dikes trend NNE, dip steeply east and west, the largest dike is more than 1OO m long and 90 m thick, most are 6-35 m thick.

The pegmatites are unzoned and are composed of 20% spodumene, 41% potash and sodium feldspar, 32% quartz, 6% muscovite and 1% accessory minerals, over 100 different minerals; many rare and some unique to the pegmatites.