The area is underlain by volcanic rocks of the Jurassic age Hazelton Group. The Oriole occurrence consists of a band of quartz in a shear zone in porphyritic andesite. A sample of mineral- ized quartz assayed 1.03 grams per tonne gold, 1652.57 grams per tonne silver, 7.0 per cent lead and 8.0 per cent zinc (Lay, 1937).