The Mary Mac (Main) occurrence is located on the east side of Truax Creek, approximately 4.5 kilometres southwest of the creek mouth on Carpenter Lake and 20 kilometres east of Goldbridge.
The country rocks are Mississippian to Jurassic Bridge River Group metasediments and volcanics. Fine-grained chloritic meta-andesite and fragmented basalts and flows are intercalated with argillite, chert, phyllite and minor limestone. This package, represented mainly by bedded cherts on the property, is cut by hornblende-feldspar porphyry dikes probably related to the Tertiary to Cretaceous Bendor pluton.
There are two distinct types of occurrences: earlier molybdenum mineralization followed by later stibnite-gold mineralization. The molybdenum is concentrated as selvages along the margins of quartz stringers forming a reticulate pattern in the hornblende feldspar porphyry. The mineralization extends into the country rock, where molybdenum is fine grained and appears as a purplish-grey sheen.
The gold-bearing quartz-carbonate-stibnite veins transect all the rock types; they are well defined in the faulted metavolcanics and become more diffuse as they crosscut the porphyry stockwork. The veins range from 0.5 to 2 metres in width, dipping 40 to 70 degrees north along the general west-northwest trend that the dikes, fractures and shears all follow. Mineralization consists of massive coarsely crystalline stibnite with associated gold, arsenopyrite, pyrrhotite, chalcopyrite, limonite and traces of tetrahedrite and/or jamesonite(?). High but spotty values of silver are reported. Chloritic alteration is widespread with local sericite and abundant pyrite.
Assay values quoted for the main zone were 10.3 grams per tonne gold over 0.75 metre and 3.4 grams per tonne gold over 5 to 6 metres. The Main zone is approximately 100 metres wide. Assays in the North zone run 1.7 to 3.4 grams per tonne gold over 4 to 5 metres in quartz-stibnite veins; this was the source of ore used in an antimony mill that operated in 1974, producing approximately 4 tonnes of rough stibnite concentrate per day. The grade of stibnite was reported at 20 per cent over 2.1 metres with reserves of 13.6 to 18.1 thousand tonnes (1974 Application for Production Permit).
Other workings on the property include several adits.
In 1983, indicated reserves for the Main zone were reported to be 22,300 tonnes grading 7.4338 grams per tonne gold or 78,500 tonnes of ore grading 2.8927 grams per tonne (Assessment Report 11647).
Indicated reserves for the North zone in 1983 were reported to be 10,800 tonnes grading 5.256 grams per tonne gold or 39,200 tonnes grading 2.3328 grams per tonne gold (Assessment Report 11647).
In 1980, Keron Holdings completed a program of geological mapping and geochemical sampling on the area as the H.J. claims. In 1981, Hudson Bay Oil and Gas completed a program of rock and soil sampling. In 1983, a total of 8 diamond drill holes were put down by Andaurex Resources on the area. In 1986 and 1987, Pilgrim Holdings, on the behalf of Keron Holdings, completed programs of trenching, geochemical sampling, geological mapping, ground magnetic and electromagnetic surveys and 11 diamond drill holes, totalling 998 metres.
In 1987, diamond drilling (Drill Hole T87-8) on the western end the Main zone trend intercepted several narrow quartz-stibnite veinlets in otherwise barren rock. One vein assayed up to 15.6 grams per tonne gold (Assessment Report 16378).
In 1999, A.B. Hemingway staked the area as the Merry Me and Mary claims and completed a ground magnetometer survey the following year. In 2002, an air photo and satellite image interpretation program was completed. In 2005 and 2006, Action Minerals completed programs of prospecting and airborne magnetic and electromagnetic surveys the area as the Williams property. In 2009, A.B. Hemingway completed a program of rock, silt and soil sampling. In 2011 and 2012, Nubia Exploration optioned the property and completed rock and soil sampling, prospecting and a ground magnetometer survey. Zimtu Capital Corporation later optioned the property. In 2014, on behalf of Zimtu Capital Corporation, A.B. Hemingway conducted a rock sampling geochemistry program on the Mary Mac East zone. Four rock samples were collected, three of which were sent for assay; the old Paly Vein/North adit was located and a new target of massive sulphide float was identified at the end of the east road.