Chvaleticeite is a monoclinic magnesium with formula: (Mn2+, Mg)·6(H2O). It occurs in the oxidized zone of manganese silicate deposits with pyrite that have undergone regional and contact metamorphism. It is defined as the manganese dominant member of the hexahydrite group.
Chvaleticeite is named after the city Chvaletice , Bohemia. Chvaleticeite and minerals like it have been studied for their hydrogen bonding properties as they are predicted to form in the relative environments of Mars and other bodies in the solar system.