Ore styles observed at Mufulira, Zambia - Samples from the lower, or 'C' Orebody (left image) and the middle, of 'B' Orebody (right image). Both are silicified quartzites, in which bedding is not obvious, in contrast to the bedded, variably argillaceous arenites stratigraphically above and below each. Copper sulphides are dominantly bornite in the 'B' Orebody, but with significant chalcopyrite also in the 'C' Orebody (e.g., left arrow on the right image). These sulphides occur as both fine 'flyspeck' disseminations (e.g., lower left and upper right arrow heads, and virtually all other fine dark specks in the insets and main images), and as aggregates (e.g., arrowhead in upper inset). These aggregates and 'flyspecks' are locally concentrated in diffuse bands parallel to the 'bedding' in the enclosing rocks (e.g., the band across the image immediately below the inset area on the left image). The surface of the left image is perpendicular to 'bedding', while the right image is subparallel to bedding to the left, and cutting it to the right. Scale bars are in centimetres, graduated in millimetres. Samples collected by Mike Porter during an earlier visit in 1992. Photographs by Mike Porter.
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