The geology of the region consists of (?)Hadrynian to Paleozoic Snowshoe Group rocks. The Snowshoe Group is an assemblage of dominantly metasedimentary rocks within the Barkerville Terrane of south-central British Columbia. The metasedimentary rocks consist primarily of marble, quartzite and phyllite. In the Yanks Peak area these rocks comprise the Keithley and Harveys Ridge successions, but further to the east they remain undifferentiated. Metamorphism of the region varies from chlorite to sillimanite and higher grade. Gold-bearing quartz veins occur only in greenschist facies rocks.

The Boulder Ledge showing consists of a single quartz vein discovered during tunnelling operations in 1874. While descriptive information is scanty, the vein was reported to contain galena and gold mineralization. Because of its location with respect to similar veins in the area, it is expected that the vein is hosted by Harveys Ridge succession, Snowshoe Group rocks.

The 1886 Minister of Mines Annual Report states the location of the Boulder Ledge "is on the point below Smith and Anderson’s hydraulic diggings on Little Snowshoe Creek, where there is a Chinese cabin, 200 yards below Smith’s. In 1874, Mr. Haywood ran a tunnel to find the high bedrock bench of the channel and found this ledge. It contained a good deal of galena and Mr. Haywood thought gold."