The Great Ohio property is located on the west side of the Rocher Deboule Range, 10 kilometres south of South Hazelton. It is located south of the Rocher Deboule mine (093M 071).
The property is underlain by porphyritic granodiorite of the Rocher Deboule stock which is one of the Late Cretaceous Bulkley Intrusions. The stock has been dated at 72 million years (Geological Survey of Canada Open File 2322). The stock intrudes hornfelsed sedimentary rocks of the Middle Jurassic to Lower Cretaceous Bowser Lake Group.
The main vein strikes 050 degrees, dipping 70 degrees northwest, parallel to the granodiorite-sediment contact. The quartz vein is up to 120 centimetres in width and is mineralized with scattered minor chalcopyrite, galena, sphalerite, pyrrhotite, arsenopyrite and pyrite. Two parallel subsidiary structures contain quartz, hornblende and chalcopyrite.
A 13-centimetre wide sample of typical material from one of these assayed 0.2 gram per tonne gold and 0.62 per cent copper (Geological Survey of Canada Memoir 223).
In 2007, a grab sample (RD07-004) assayed 0.12 gram per tonne gold and 0.547 per cent copper (Burgoyne, A.A., Kikauka, A. (2007-12-18): Technical Report on the Rocher Deboule Property).
The Great Ohio claim was staked in 1910. An adit, at elevation 1,372 metres and likely dating to this time, explores the three parallel shear zones.
During 2001 through 2007, Rocher Deboule Minerals Corporation completed programs of rock and soil sampling, prospecting, geological mapping and an airborne (electromagnetic, magnetic and radiometric) geophysical survey on the area as the Rocher Deboule property.