The Rathmullen Group, which includes the Maple Leaf (Lot 1502) claim, is located northwest of Thimble Mountain, 1.5 kilometres northeast of the B.C. (Lot 882) claim (082ESE060).

Turn of the century workings on the Maple Leaf claim, which was Crown granted in 1899, consists of a 40-metre shaft with a drift up to 22 metres. The drift passed through a 8.5-metre wide ore zone. Mineralization consists of quartz gangue carrying pyrrhotite, chalcopyrite and gold values within diorite. Thirty three tonnes of ore were reported being shipped to a smelter in 1904. The claim was owned by W.M. Gowans in 1928.

In 1991, Pan Orvana Resources Inc. conducted mapping and geochemical sampling east of this showing. However, a sample of quartz-calcite vein material on a dump at this site returned an assay of 1.98 per cent copper, 327.9 grams per tonne silver, 3.29 gram per tonne gold and 0.29 per cent zinc (Assessment Report 22105).

The area is underlain by limestone of the Triassic Brooklyn Group. These rocks are cut by diorites of the Jurassic-Cretaceous Wallace Creek Pluton and porphyries of the Eocene Coryell Intrusions.