Fianelite, Mn2V(V,As)O7.2H2O
Fianel, Val Ferrera, Grischun (Graubünden), Switzerland
Large fianelite mono-crystal; the a-axis is parallel to the striations.
SEM picture by "REM-Labor", Universitaet Basel.
Fianelite. The a-axis is parallel to the striations
Brugger, J. and Berlepsch, P. (1996): Description and crystal structure of fianelite
Mn2V(V,As)O7.2H2O, a new mineral from Fianel, Val Ferrera, (Graubünden, Switzerland). Amer. Mineral. 81, 1270-1276.