The Prospect Creek showing is located on the west bank of Prospect Creek, approximately 0.8 kilometres from its confluence with Spius Creek.

The area is underlain by Middle and Upper Cretaceous Kingsvale Group mafic volcanics (redefined to the Spius Creek Formation of the Spences Bridge Group; Geological Survey of Canada Map 42-1989). Rocks close to the showing comprise volcanic breccia and aphanitic, amygdaloidal, vesicular, porphyritic and spherulitic andesites and basalts.

Two parallel amber to brown perlite layers are exposed over 6 by 3 metres and separated by spherulitic, glassy rhyolite (possibly dykes or chilled contact zones) striking 030 degrees and dipping 40 to 60 degrees southeast (Assessment Report 13336). Another two metre wide perlite layer is exposed 30 metres to the south (upslope). Perlite layers are terminated by flat-lying andesite.

Perlite displays pitchy lustre and contains scattered feldspar and quartz crystals and spherules.