The Gold-Thorium showing is located at the foot of the Grand Canyon on the Fraser River, approximately 72 kilometres east of the town of Prince George. The showing is in the Cariboo Mining Division.
The area is underlain by platformal sedimentary rocks of the Cariboo terrane. These rocks comprise limestone, shale and sandstone of the lower Cambrian Mural Formation (Gog Group), which are poorly exposed in the Fraser River Valley.
The showing comprises fluvial concentrates of black sand in which radioactivity, likely attributable to thorium, has been identified. Analysis of this black sand returned 0.31 per cent uranium (Geological Survey of Canada Economic Geology vol. 16, p.45). The source of the radioactive sand may be gneissic rocks of the Omineca Belt to the southwest.
"Data from the Cariboo mining district indicate that supergene leaching of gold dispersed within massive sulphides by Tertiary deep weathering followed by Cenozoic erosion is the most likely explanation for the occurrence of coarse gold nuggets in Quaternary sediments" (Exploration in British Columbia 1989, page 147).