Manganese content of the Shady dolomite in Bumpass Cove, Tennessee

Abstract

The Shady dolomite in Bumpass Cove, Tennessee, contains deposits of hydrothermal sulphide minerals, and its residual clay contains oxidized manganese deposits. New chemical evidence bearing on the source of this manganese is presented.Chemical analyses of isolated components of sulphide-bearing dolomite show that the percentage of manganese is highest in country-rock dolomite unaffected by hydrothermal action, and that the manganese is present as carbonate. Manganese determinations on samples from a drill hole show that 43 feet of beds, about 100 feet above the base of the Shady dolomite, average 0.6 per cent manganese oxide, and that adjacent beds carry smaller amounts. Manganese carbonate, deposited with the original carbonate rock, is therefore considered to be the source of the manganese deposits of Bumpass Cove.