The Molly occurrence is located within diorite and quartz diorite of the Cretaceous Coast Plutonic Complex.

Small amounts of molybdenite are reported over a 300 metre area. The mineralization is disseminated in aplite and fine- grained granitic dykes, in quartz-filled joints, and in quartz veins.

The main workings are located 500 metres west of Haslam Lake. An open cut and an adit expose three aplite dykes cutting quartz diorite. The dykes strike 040 degrees and dip 60 degrees north, and range from 10.0 to 46.0 centimetres in width. Small flakes of molybdenite are associated with pegmatitic quartz and feldspar on the footwall side of the largest of the dykes.

About 270 metres southeast of the main workings, the dump of a sloughed trench contains molybdenite and chalcopyrite in 1.3 to 5.0 centimetre wide quartz stringers. Twenty five metres southwest of the trench, stripping over 10 metres exposed a quartz vein stockwork in quartz diorite. The quartz veins range from 0.2 to 3.8 in width and are spaced between 10.0 to 61.0 centimetres apart, and contain molybdenite and chalcopyrite. The highest of 7 chip samples assayed 0.2 per cent molybdenite (Geological Survey of Canada, Economic Geology Report No.20, page 257).

Thirty metres southwest from this showing, a 050 degree striking quartz vein ranges in width from 5.0 to 15.0 centimetres and contains minor molybdenite and chalcopyrite.

North of the main workings, a 15.0 to 30.5 centimetre wide quartz vein strikes 050 degrees and dips 75 degrees north, and contains magnetite, molybdenite and molybdic oxide.

Several other small occurrences are reported within the area.