The Orphan Boy (adit) occurrence is located on the northeast bank of Barret Creek, a small south- flowing tributary of McCullock Creek, at an elevation of approximately 1765 metres.
The area is underlain by metasedimentary rocks interlayered with mafic volcanic rocks of the Cambrian to Devonian Index Formation (Lardeau Group). The metasediments consist of quartzites, schists, phyllites, calcareous schists, carbonates and fine clastic rocks. The metavolcanics are tholeiitic flows and mafic tuffs metamorphosed to greenstone and chloritic phyllite. The rocks exposed are correlated to Hoy's (Bulletin 71) metavolcanic-phyllite division and quartzite schist division of probable lower Paleozoic Hamill Group and upper Proterozoic Horsethief Creek Group (Assessment Report 11860).
Phase 2 and phase 3 folds are developed in an inverted stratigraphic panel. Predominant schistosity is east to south- east with dips commonly at 20 degrees east.
Two sets of quartz veins occur in the area. The commonly mineralized discordant veins strike 010 to 020 degrees and dip 70 to 85 degrees west. They range from 0.15 to 4 metres in width. Barren veins, concordant with bedding, although with steeper dips, are up to 3 metres thick. The mineralized veins consist essentially of milky quartz with pyrite, lesser pyrrhotite and free gold. Scheelite occurs in some of the auriferous veins.
In the Orphan Boy shaft area several north-northeast quartz veins occur within pelitic schists, while at the adit area, 150 metres to the east, quartz veins are closely associated with greenstones.
In 1896, nine samples are reported to have assayed from 17.1 to 2189 grams per tonne gold (Property File - Stanmack Mines Ltd. [1963-04-03]: Correspondence re: Stanmack Property).
In 1984, a sample from a 35 centimetre wide vein assayed 8.37 grams per tonne gold (Assessment Report 11860).
The area has been explored since the discoveries of placer gold in the area in 1865 and gold-bearing quartz veins in the headwaters of McCulloch Creek in 1885. During 1896 through 1900, the Ole Bull (MINFILE 082M 080) and Orphan Boy groups were developed including a 13.5-metre deep shaft and a 21.6-metre adit on the Orphan Boy group. During this time, 1886 tonnes of ’ore’ grade material were reportedly dumped nearby.
