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Chalveticiete (Chalveticeite Chalveticeite) Chvaleticeite is named after the city Chvaletice, Bohemia in the Czech Republic. Chvaleticeite is a monoclinic hexahydrite mineral discovered to form by pyrite and rhodochrosite that have undergone regional and contact metamorphism. It is defined as an Mn dominant member of the hexahydrite group. Chvaleticeite and minerals like it have been studied for their hydrogen bonding and incongruent melting properties as they are predicted to form in the relative environments of Mars and other astral bodies in the solar system.

Structure
The structure in Chalveticeite is due to hydrogen bonding in metallic sulfates. Due to the minute size of the grain of chvaleticeite typical single crystal methods could not be used. Through analogy with hexahydrite the Guinier powder diffraction method was used to identify the following structural parameters. Space group C 2/c. a = 10.05(2), b = 7.24(2), c = 24.3(1) Å; β = 98.0(2)°, V = 1754 Å3, Z = 8, Dx = 1.84g•cm-3; a : b : c = 1.3881 : 1 : 3.3564.

Composition
Chvaleticeite has an empirical formula of (Mg, Mn)SO4•6H2O and is a member of the Hexahydrite group with the space group C2/c. Chemical analysis was carried out using classical chemical methods. Sulfate was determined gravimetrically as a BaSO4, MnO was determined using titration, MgO was determined by EDTA titration and CaO, Fe2O3, K2O and Na2O using AAS. The H2O was determined by the modified Penfield method. The performed analysis produced the following result: MnO 15.81, MgO 6.41, CaO 0.04, FeO traces, Fe2O3 0.10, Al2O3 traces, K2O 0.005, Na2O 0.011, SO3 31.48, P2O5 traces, H2O+ 0.37, H2O- 45.22, insoluble residue 0.36, sum 99.81 weight %.

Special Characteristic
Chvaleticeite was discovered in an affluent sulphate paragenesis in the oxidation zone of the Upper Proterozoic volcano-sedimentary deposit of pyrite-manganese ores at Chvaletice. It was found in association with melanterite (by partial dehydration it can form) Mg-jokouite, Mg-ilesite, rozenite, copiapite and gypsum. This paragenesis allows heptahydrates and tetrahydrates to dominate over pentahydrates and hexahydrates. This makes Chvaleticeite occurrences very rare. Chalveticeite is completely soluble in water.