The Tess occurrence is located north of Twinkle Lake, approximately 6 kilometres south of Nadina Lake.
Regionally, the area is a part of the Stikine terrane, which consists of Triassic island arc assemblages, Lower to Middle Jurassic volcaniclastics and marine sediments, Upper Jurassic to Lower Cretaceous sediments, and Late Cretaceous to Tertiary volcanic arc assemblages.
Locally, the area is underlain by the Middle Jurassic Smithers and Lower Jurassic Telkwa formations of the Hazelton group. The Hazelton Group formations are overlain by Cretaceous volcanics of the Kasalka group. The Kasalka Group volcanics primarily consist of hornblende-feldspar porphyritic andesite flows and pyroclastic rocks
Mineralization consists of dusty, fine-grained disseminated pyrite in hornblende-feldspar porphyritic andesite lavas and breccias. Pyrite mineralization is generally more abundant in the brecciated andesitic lavas and pyroclastic rocks. The andesitic volcanics are strongly silicified and have weak to moderate epidote-chlorite alteration.
In 2006, Rimfire Minerals Corp. completed a program of surface geochemistry, prospecting and mapping on the Patti Walker Group. One of the bed rock samples returned values up to 0.13 gram per tonne gold (Assessment Report 29644).