Formula: Al3(PO4)(OH)6.6H2O Amorphous
Evansite is a poorly described mineral forming white to ocherous opalline crusts associated with other phosphates formed by surface weathering.
DODGE COUNTY: Evansite was tentatively identified by x-ray analysis as microscopic anhedral grains in the oolites of the Mayville iron ore. These are exposed in sec. 1, 12 and 13 T.11N. R.16E. east of Neda (Hawley and Bevan, 1934).