The Castleton (L.14571) occurrence is located on the south side of Bonanza Creek, approximately 300 metres southwest of its junction with Mitchener Creek.

The area is underlain by an east-trending belt of greenstones, tuffs, limestones and argillaceous sediments of the Carboniferous to Permian Mount Roberts Formation that have been intruded by a Middle Jurassic porphyritic granite and syenitic to monzonitic rocks of the Eocene Coryell Plutonic Suite.

Locally, a narrow, irregular, quartz-filled shear zone hosts pyrite and chalcopyrite. The shear zone dips steeply west and has been traced along strike for approximately 25 metres.

Samples are reported to have yielded from 3.4 to 30.8 grams per tonne gold (Property File - Taff Resources Ltd. [1990-10-12]: Geological Evaluation of the Seal Claim Group).

During 1983 through 1986, Rex Silver Mines Ltd. conducted programs of rock and silt sampling, geological mapping and ground geophysical surveys on the area as the Joy 1-4 claims. During 1988 through 1990, Taff Resources Ltd. conducted programs of rock and soil sampling, geological mapping and a 23.6 line-kilometre ground electromagnetic (VLF) survey on the area as the Seal claims.

During 2003 through 2005, Kootenay Gold Inc. completed a program of geological mapping and prospecting on the area.