The Tyon occurrence is located near the top of the ridge separating the east and west forks of Last Creek, a tributary of Tyaughton Creek.

The area is underlain by mainly sedimentary rocks of the Upper Triassic Tyaughton Group and Lower to Middle Jurassic Last Creek Formation. These have been intruded by Paleocene to Eocene feldspar porphyritic intrusives.

Locally, bands or zones, 1 to 2 metres wide, of garnetiferous limy skarn and pyritic skarn host gold values. In 1981, a rock chip sample (DTY-03) assayed 1.35 grams per tonne gold (Assessment Report 09753).

In 1981, Prism Resources Limited completed a program of geochemical sampling and geological mapping.