Mineral investigations near Bodmin, Cornwall. Part 4, drilling at Royalton Farm

Fourteen inclined percussive drillholes have shown that weak tin mineralisation persists into the hangingwall slates of the Royalton elvan for a distance of at least 50 m. Geochemically anomalous tin values are recorded along the full strike length of the former opencast workings of the Old Castle-an-Dinas Mine, but the richest concentrations are found near the western, circular-shaped pit. Even here, the grades rarely reach economically interesting levels, and then only over intervals of 1.5 m. Immediately east of the openworks there is a marked enrichment in copper and nickel, but at levels well below those of economic significance.