The Boulder (Skerl) occurrence is located on or near Schist Creek, a north -flowing tributary of Ure Creek.

The area is underlain mainly by andesitic volcanic rocks consisting of flows and breccia that have been intruded by andesitic dikes of the Upper Triassic Cadwallader Group and greenschist metamorphic rocks of the Cretaceous to Tertiary Slollicum Schist.

Locally, massive banded pyrite and magnetite along with lesser chalcopyrite, malachite, azurite, galena and sphalerite mineralization is hosted by a banded, siliceous, pyritic tuff and/or epidote-diopside-garnet calc-silicates which, in places, contains up to 20 per cent rhodonite. The mineralized zone has been reportedly exposed over 90 metres.

In 1983, a grab sample from the main zone of mineralization assayed 1.5 per cent copper (Assessment Report 11529).

In 1988, an outcrop sample assayed 0.3 per cent copper and 0.15 per cent zinc (Property File - Green Lake Resources Ltd. [1988-03-29]: News Release - Winter Programs completed on Lill, Golden Plug and Native Properties).

The area has been historically explored in conjunction with the nearby Lake Adit (MINFILE 092JSE009) occurrence. During 1958 through 1960, the area was prospected and sampled by A. Skerl as the Tug claims. In 1969, the area was explored by Cerro Mining Company of Canada Ltd. In 1983, Hightest Resources completed a program of rock and soil sampling. In 1985, Lawrence Mining examined the property. Green Lake Resources Ltd. completed a detailed exploration program during 1986 through 1988 on the area as the Lill claims.