author(s) : Frondel and Ito
date of publication : 1972
source : Neues Jahrb.Min.Abh. (123) p.111-115
formula : (Mg5,4Mn2,2Fe1,7 2 +ZnAl0,7Fe0,7 3 +)(OH)16 (Si7,1Al0,9)O20
comments about the origin : Etiquette Harvard University Frondel 1975
This type specimen, kept in the Museum of Ecole des mines de Paris, has been indexed by Dr Guillemin.
(C) BRGM, ENSMP