The Tokyo showing, which occurs on the old Crown granted Mammoth (Lot 1410) claim, is located on the northwest slope of Thimble Mountain, 1 kilometre east of the B.C. (Lot 882) claim (082ESE060).

The showing is near turn of the century workings, consisting of old shafts and trenches. (The Mammoth was Crown granted in 1900.) In 1992, H. Hoehn commissioned Crownex Resources Ltd. to conduct a geophysical survey and geochemical sampling. Hoehn previously drilled the area and encountered chalcopyrite bearing skarn. Mineralization near the old 8-metre shaft consists of pyrrhotite, chalcopyrite, pyrite, sphalerite and hematite within quartz and calcite veins; mineralized pods in a skarn zone occur along an intrusive and limestone contact. A sample assayed over 1.0 per cent copper, 25.4 grams per tonne silver, 1.07 grams per tonne gold and over 1.0 per cent zinc (Assessment Report 22707).

The area is underlain by limestone and marble of the Triassic Brooklyn Group; these rocks are cut by granodiorite of the Jurassic Nelson Intrusions and alkaline syenite of the Eocene Coryell Intrusions.