Northupite Na3Mg(CO3)2Cl Isometric

Description:

DODGE COUNTY: A grain 0.6 cm. long found in the matrix of the Mayville oolitic iron formation was tentatively identified by Hawley and Beaven (1934) as northupite. The mineral was a cube modified by a dodecahedron along one edge, had a saline taste, a refractive index of 1.5145 and effervesced in HCl. The iron formation is exposed in old mines and outcrops in sec. 1, 12 and 13 T.11N. R.16E., east of Neda.

Return to Wisconsin Mineral List