As nouns the difference between anhydrite and karstenite
is that anhydrite is (mineral) a saline evaporite consisting of anhydrous calcium sulfate (gypsum) while karstenite is (mineralogy|archaic) anhydrite.
anhydrite
Noun
(-)
(mineral) A saline evaporite consisting of anhydrous calcium sulfate (gypsum).
karstenite
English
Noun
(-)
(mineralogy, archaic) anhydrite