Ref.: Dana, E.S. (1892) System of Mineralogy, 6th. Edition, New York: 899.
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: 432, 434, 449.
A salt mine.