The Ace occurrence is located on the southwest flank of One Ace Mountain about 10 kilometres south of the Yukon-British Columbia border, 158 kilometres north of the community of Dease Lake.

The showing is underlain by Lower Cambrian Atan Group limestones and quartzites. Spotty mineralization occurs along a zone five kilometres long, paralleling the northeast striking limestone-quartzite contact and about 150 to 300 metres within the limestone. Closely-spaced quartz veins and lenses contain bornite, chalcopyrite, chalcocite, malachite and azurite. Individual veins within the zone show no apparent structural control.