Category: Borate sulfates

Borate sulfate
Borate sulfates are mixed anion compounds containing separate borate and sulfate anions. They are distinct from the borosulfates where the borate is linked to a sulfate via a common oxygen atom.
Sturmanite is a rare sulfate mineral with the chemical formula Ca6Fe3+2(SO4)2.5(B(OH)4)(OH)12 · 25 H2O. It crystallises in the tetragonal system and it has a Moh's hardness of 2.5. Sturmanite has a br
Fontarnauite is a relatively recently described, rare sulfate, borate mineral with the chemical formula (Na,K)2(Sr,Ca)(SO4)[B5O8(OH)]·2H2O. It is found in an evaporite boron deposit. It coexists with
Charlesite is a sulfate mineral of the ettringite group. Charlesite was named in 1945 after Dr. Charles Palache mineralogist and professor at Harvard University for his work on minerals. This mineral