Ferrian Chlorospinel from Carneal, Co. Antrim

P. A. Sabine, G. A. Sergeant1 and B. R. Young
Institute of Geological Sciences, London S.W. 7
with chemical analysis by G. A. Sergeant
X-ray data by B. R. Young
1Laboratory of the Government Chemist, London, S.E. 1.

Summary: A Tertiary dolerite plug at Carneal, Co. Antrim has been contaminated by Chalk with the production of calc-silicates and related minerals. In a larnitespinel-rock the spinel is of the unusual ferrian variety. It has the composition (Mg6·82Fe0.76″Mn0·12Ni0·01Zn0·01)(Al11·2Fe4.94‴Ti0·03)O32. The spinel, which is brown, has: n, 1·862; D, 3·97; a, 8·1905 Å. A chemical analysis and powder data are given, the implications of experimental data are briefly discussed, and the nomenclature is reviewed.

Mineralogical Magazine; September 1968 v. 36; no. 283; p. 948-954; DOI: 10.1180/minmag.1968.283.036.05
© 1968, The Mineralogical Society
Mineralogical Society (www.minersoc.org)