The Cretaceous Horsethief Batholith intrudes Middle Proterozoic sediments of the Purcell Supergroup. The intrusion is zoned from fine-grained/medium-grained granodiorite to coarse-grained quartz monzonite. East trending aplite dykes cut the intrusion.

The Spicebox showings all occur in coarse-grained quartz monzonite within 100 metres of the intrusive contact. In the area of the showings, the quartz monzonite is moderately fractured with the main set of fractures trending about 305 degrees. A secondary set trends about 035 degrees, some of the fractures being quartz-filled. It is along fracture faces that chalcopyrite, bornite, molybdenite and pyrite mineralization is found. Secondary alteration along fractures includes silicification, sericitization and pink k-feldspar alteration. Three showings have been found.

Showing 1 is the most northern showing. A fracture system trending northwest contains pyrite and chalcopyrite blebs along fracture faces with prominent k-feldspar alteration. Fracture density is approximately 1 every 1.2 metres.

Showing 2 occurs about 240 metres to the south of Showing 1. Chalcopyrite, bornite and pyrite occur in northwest trending fractures. Dominant secondary alteration of fractures includes k-feldspar, sericite and quartz. Fracture density is one every 15 centimetres. Mineralized fractures were noted over an outcrop area of 30 metres by 15 metres.

Showing 3 occurs about 240 metres south of Showing 2. Molybdenite was noted as spotty disseminations in two of the northeast trending, 5 centimetre wide quartz veins.

Canadian Johns-Manville Company Limited staked and investigated a number of claims in the area in 1970, including the Slide, Annette and Blue. It is reported that 739 geochemical samples were taken in 1970 (Geology, Exploration and Mining in BC 1970, page 469). In 1971, Canadian Johns-Manville completed further geochemical, geological and geophysical surveys on its Slide group of claims (Geology, Exploration and Mining in BC 1971, page 426). It was reported that K. Schrijver found the Blue showings in 1971. In 1972, the company completed further surveys on its Slide group including mapping and geochemical sampling (Geology, Exploration and Mining in BC 1972, page 74). The company returned in 1973 and conducted further surveys including some detailed mapping on the Blue claims, Spicebox showings (Geology, Exploration and Mining in BC 1973, page 92).