The Mary occurrence is located near the summit of Mount Spencer, in the headwaters of Museum Creek.

Pillowed and massive andesite and associated volcaniclastics of the Upper Triassic Karmutsen Formation are intruded by gabbroic and basaltic dykes and feldspar porphyry dykes. The volcanics are overlain by thin to medium-bedded limestone, likely of the Triassic Quatsino Formation.

Several types of mineralization occur in an east-west trending area, measuring approximately 1000 by 400 metres, south of Mt. Spencer. These include: pyrrhotite, chalcopyrite, molybdenite and minor sphalerite and galena within quartz veins and shear zones in andesite; basalt dyke margins with pyrrhotite; copper-bearing skarn zones in limestone and; chalcopyrite, pyrrhotite and pyrite near feldspar porphyry dyke contacts.

In Zone 1, disseminated to massive pyrrhotite, pyrite and chalcopyrite, up to 0.6 metre thick, occur along fractures and joint surfaces over a 61 to 122 metre wide by 366 metre long area. The average grade of the zone is 0.15 per cent copper, including a 6 metre section of 0.63 per cent copper (Assessment Report 8177). A drill hole intersected 180 grams per tonne silver and 10.30 per cent copper over 0.8 metres (Assessment Report 6134).

Zone 2, located 250 metres to the northeast of Zone 1, measures 15 by 300 metres and contains pods and disseminations of chalcopyrite and pyrrhotite. The average grade of the zone is 0.8 per cent copper, including a 6 metre section of 0.97 per cent copper (Assessment Report 8177).

One hundred meters north of Zone 2, Zone 3 contains disseminated and massive pyrrhotite and minor chalcopyrite on fracture planes in andesite.

Zone 3a, about 600 metres to the east of Zone 1, contains dis- seminated and massive chalcopyrite, pyrrhotite and molybdenite mineralization in narrow veins. A drill hole intersection contained 24.7 metres of 1.22 per cent copper and 0.066 per cent MoS2, includ- ing 3.1 metres of 71.7 grams per tonne silver and 6.56 per cent copper (Assessment Report 8177).

There are several other small mineralized zones in the area. Pat's vein, located 100 metres south of Zone 3a, is a highly oxidized, chloritized and fractured quartz vein near a feldspar porphyry dyke. It contains pyrrhotite, pyrite and chalcopyrite and assayed 0.61 per cent copper and 1.1 grams per tonne gold (Assessment Report 8177). Ball's vein, located 350 metres northwest of Zone 1, is a 40 centimetre by 50 metre quartz vein containing galena, pyrite and chalcopyrite. A 20 centimetre sample assayed 221.5 grams per tonne silver, 0.7 per cent copper, 1.21 per cent lead and 0.5 per cent zinc (Assessment Report 14470).

In 1991, J.L. Zockodnik completed a prospecting program on the Fitz 2-9, Post, Fitzone and Fitzemal claims. In 1997, The area was explored as the Toy and Toya claims by L. Crittenden on the behalf of E.W. Hayes. A geochemical program of 21 rock samples, 51 soil samples, 2 steam sediment samples and 1.5 kilometres of geochemical soil grid lines was completed. In 2006, the area was prospected by D.J. McLelland as the Lan claim.