Stevensite

Brown alteration product partially replacing white pectolite. From the Upper New Street Quarry, Patterson, New Jersey. *(Image courtesy John Betts; unauthorized reproduction is prohibited.)*

Formula: (Ca,Na)_xMg_3-x(Si₄O₁₀)(OH)₂ Monoclinic

Description:

Stevensite is a massive white clay mineral. IMA lists its species status as questionable.

DODGE COUNTY: A white waxy mineral forming elongated grains in the matrix of the Mayville iron ore was tentatively identified as stevensite by Hawley and Beavan (1934) based on optical and microchemical tests. This iron ore was mined in sec. 1, 12 and 13 T.11N. R.16E., east of Neda.