<P> Gypsum is a common mineral , with thick and extensive evaporite beds in association with sedimentary rocks . Deposits are known to occur in strata from as far back as the Archaean eon . Gypsum is deposited from lake and sea water , as well as in hot springs , from volcanic vapors , and sulfate solutions in veins . Hydrothermal anhydrite in veins is commonly hydrated to gypsum by groundwater in near - surface exposures . It is often associated with the minerals halite and sulfur . Gypsum is the most common sulfate mineral . Pure gypsum is white , but other substances found as impurities may give a wide range of colors to local deposits . </P>
<P> Gypsum is a common mineral , with thick and extensive evaporite beds in association with sedimentary rocks . Deposits are known to occur in strata from as far back as the Archaean eon . Gypsum is deposited from lake and sea water , as well as in hot springs , from volcanic vapors , and sulfate solutions in veins . Hydrothermal anhydrite in veins is commonly hydrated to gypsum by groundwater in near - surface exposures . It is often associated with the minerals halite and sulfur . Gypsum is the most common sulfate mineral . Pure gypsum is white , but other substances found as impurities may give a wide range of colors to local deposits . </P>
where does gypsum often form ( site 3 )
where does gypsum often form ( site 3 )
in association with sedimentary rocks
in association with sedimentary rocks