Old borax mine.
Refs.: 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: 359.
Tschernich, R. (1992): Zeolites of the World, 64.
http://www.baymin.org/History/First_Field_Trip.html