Barytocalcite is an anhydrous barium carbonate mineral Ca with alstonite , that is to say the three minerals have the same formula but different structures. pseudomorphs
Barytocalcite crystallizes in the monoclinic crystal system accumulations of transparent white to yellow to grey aggregates of slender prismatic crystals. It has a Mohs hardness of 3.64 to 3.71.
It was first described in 1824 for an occurrence in the Blagill Mine (Cumberland , and named for its composition.