GYPSUM HAS BEEN MINED FROM 8 SEPERATE BEDS 1-1.5 FT THICK INTHE CHUGWATER FM. A MILL WAS BUILT IN 1916 TO MAKE STUCCOBLOCKSLOCATED IN STUCCO?ANAYLSIS CAO= 33.74% SO3=43.9% SIO2=.01% MN=.98% FE2O3+AL2O3=0.17% H2O = 19.50%WYO GEOL SURV BULL #50 1966 P 98