Fuller's earth and other industrial mineral resources of the Meigs-Attapulgus-Quincy District, Georgia and Florida

The Meigs-Attapulgus-Quincy district, Georgia and Florida, has been the leading producer of fuller's earth in the United States since 1895. The deposits occur in discontinuous beds and lenses in the Hawthorn Formation of middle Miocene age. The fuller's earth, in the vicinities of Attapulgus, Ga., and Quincy, Fla., in the southern part of the district, consists mainly of palygorskite (attapulgite of older usage) but contains minor quantities of montmorillonite and nonclay mineral impurities, including quartz, dolomite, calcite, phosphate pellets, feldspar, and miscellaneous heavy minerals. Kaolinite occurs in the upper parts of deposits under shallow overburden, and it apparently has formed by weathering of montmorillonite, which, in turn, weathers from palygorskite. The deposits in the northern part of the district are mainly montmorillonite, hut they also contain some palygorskite and sepiolite, abundant diatoms, and several of the nonclay minerals that are present in deposits in the southern part of the district. The fuller's-earth deposits apparently formed in very shallow marine lagoons or tidal flats. The magnesium in palygorskite, sepiolite, montmorillonite, and dolomite apparently came from evaporating sea water. The silica and aluminum in the clay minerals, which apparently formed in place, probably were introduced by streams, as there is very little evidence to support the theory that volcanic ash was the major parent material of the fuller's earth. Industrial minerals other than fuller's earth that are now mined in the district include silica sand, construction sand and gravel, and raw materials for common brick. Many years ago, small quantities of limestone and dolomite were dug for use in making portland cement and building stone, and a carload or two of phosphate rock was shipped from one locality.