Witzkeite: A new rare nitrate-sulphate mineral from a guano deposit at Punta de Lobos, Chile Nestola, F. ; Camara, F. ; Chukanov, N. V. ; Atencio, D. ; Coutinho, J. M. V. ; Contreira Filho, R. R. ; Farber, G. Abstract Publication: American Mineralogist Pub Date: October 2012 DOI: 10.2138/am.2012.4109 Bibcode: 2012AmMin..97.1783N