clays  search
RTbentonite deposits
 clay
 clay mineralogy
 engineering geology
 flint clay
 fuller's earth
 insulation materials
 kaolin
 kaolin deposits
 ornamental materials
 quick clay
 refractory materials
 residual clays
 sensitive clays
 shale
 soft clays
 stiff clays
 vermiculite
SNAs of 1981, use only when of economic value; use clay for material in engineering geology. Before 1981, search clays AND deposits. Commodity. See List C.
Clays Ferry Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Ordovician
 ....Clays Ferry Formation
RTKentucky
 Indiana
 Ohio
SNMiddle and Upper Ordovician. Added to Thesaurus in 1989.
claystone  search
BTsedimentary rocks
 .clastic rocks
 ..claystone
UFclay stone
RTclay
 terrigenous materials
 mudstone