Local gypsum is largely unstudied.
Colorless clear cleavage plates and crystals over 10 cm are known to occur at Sterling Hill, but much massive white material may lie in collections unrecognized. Gypsum is most commonly associated with calcite in vein assemblages and locally may be associated with anhydrite or other minerals. In addition to the two specimens mentioned by Palache, gypsum has also been found on the 1500 and 1750 levels at Sterling Hill and as a white powder associated with hancockite, clinohedrite, and andradite from Franklin. It is part of the surficial alteration of charlesite.