The Relationship Between Euhedral and Framboidal Pyrite in Base-Metal Sulphide Ores

Joseph Ostwald and Brian M. England
The Broken Hill Proprietary Company Limited, Central Research Laboratories, Shortland, New South Wales, Australia

Summary: Specimens of layered baryte containing a range of pyrite forms, including framboids, framboidal aggregates, spherulites, polyhedra, and zoned euhedral crystals from Kempfield, New South Wales, Australia, have been examined by mineragraphy, X-ray diffraction (XRD), X-ray fluorescence (XRF), and electron-probe microanalysis (EPMA). These investigations showed that the pyrite occurred in two forms—an arsenical variety containing approximately 5% arsenic in solid solution within the pyrite and a non-arsenical variety. EPMA studies indicate that the framboids and the cores of the zoned euhedral crystals have similar levels of arsenic and a genetic relationship is deduced to exist between these forms.

Mineralogical Magazine; June 1979 v. 43; no. 326; p. 297-300; DOI: 10.1180/minmag.1979.043.326.13
© 1979, The Mineralogical Society
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