Ganomalite from Franklin, New Jersey, and Jakobsberg, Sweden: New Chemical and Crystallographic Data

Pete J. Dunn, Donald R. Peacor, John W. Valley* and Charles A. Randall†
Department of Mineral Sciences, Smithsonian Institution, Washington, DC 20560, USA
Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA
*Present address: Department of Geology and Geophysics, University of Wisconsin, Madison, Wisconsin 53706.
†Present address: Thomas Road, Rindge, New Hampshire 03461.

Abstract: Chemical analyses for ganomalite from Franklin, New Jersey, and Jakobsberg, Nordmark, Sweden, imply that Mn is an essential element and that the formula is Pb9Ca5MnSi9O33, with Z = 1 for the hexagonal unit cell. Preliminary crystal structure data confirm that Mn and Ca are ordered, as implied by the chemical analyses. Ganomalite is hexagonal, space group P3, with a = 9.82 and c = 10.13 Å. Occurrences of samples from both localities are described, together with analytical data for macedonite from Jakobsberg.

Keywords: ganomalite • Franklin • New Jersey • USA • Jakobsberg • Sweden

Mineralogical Magazine; September 1985 v. 49; no. 353; p. 579-582; DOI: 10.1180/minmag.1985.049.353.12
© 1985, The Mineralogical Society
Mineralogical Society (www.minersoc.org)