Abstract

Nickel sulfide fire assay neutron activation analysis and lead fire assay direct current plasma spectroscopy were used to determine platinum-group elements (PGE) and gold in 30 channel samples and 23 fault-related samples from the Blakeburn opencast mine, south-central British Columbia, Canada. In the majority of the channel samples concentrations of Os, Ir, Ru, Rh, Pd, and Re were below detection. Pt in the coal ranged from below detection to 170 ppb, and Au from below detection to 38 ppb. Concentrations of all the PGE, with the exception of Ru, were on average higher in the coals than in the sediments. In the deformed coal samples Os, Ru, Rh, and Re were typically below detection. Anomalous values of Pt, up to >10,000 ppb, were determined in three deformed coal samples, and Pd and Ir were comparatively enriched in the majority of deformed coal samples (up to 6,100 and 22 ppb, respectively) compared with channel samples. On the basis of SEM-EDX, and comparisons with ash and organic matter contents, it is likely that Pt and Au are present in the coal as discrete particles, precipitated from circulating ground waters on contact with the organic-rich, reducing, and low pH environment of the coal. Pt and Au distributions appear to be related to sources of the elements in ground water, i.e., interbedded volcanic units and the Tulameen Ultramafic Complex for Pt, and interbedded clastic sedimentary units for Au. Enhanced concentrations of Pt and Pd occur in coal samples associated with two faults.

First Page Preview

First page PDF preview
You do not currently have access to this article.