(Douglashall, Westeregeln, Stassfurter Kalisalzlagerstätte, Sachsen-Anhalt, Deutschland)
Ref.: Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 380, 402.