The Millie Mack property is located near the top of Blue Grouse Mountain, approximately 12 kilometres east-northeast of Burton. The property is accessible via a 24 kilometre gravel road along the north side of Caribou Creek. Four zones (Millie Mack, Black Bear, Billie P and Great Western) within an area measuring approximately 750 by 1200 metres comprise the Millie Mack property. The showings are exposed in trenches and underground workings. The main occurrence, the Millie Mack, is a deformed and boudinaged quartz vein hosted in graphitic schist of the Triassic Slocan Group. The Billie P quartz veins are reportedly (Paper 1986-1, page 351) deformed in a similar manner, while the quartz veins in the Black Bear open pit follow the bedding planes and are not strongly deformed. Bedding attitudes are shallowly dipping and undulating.
The Millie Mack veins are located at the base of a section of Slocan Group clastic sedimentary rocks which overlie mafic volcanic rocks. There are two interpretations regarding the structural relationships: Geological Survey of Canada Bulletin 161 shows the contact as a low angle thrust, and the Slocan Group strata a klippe thrust over younger volcanic rocks of the Jurassic Rossland Group (Elise Formation). The second interpretation would have the Slocan sedimentary strata in normal (unfaulted) contact with older volcanic rock (Geological Survey of Canada Open File 432). Slocan Group strata include sandstone, siltstone, argillite, tuff, andesite and volcanic breccia. They are locally calcareous and contain local pods of limestone. Rossland Group volcanics include volcanic breccia, feldspar porphyry and basalt.
Basal Slocan Group strata are highly sheared graphitic argillite which contains blocks or boudins of vein quartz mineralized with galena, sphalerite, arsenopyrite, chalcopyrite and pyrite. The graphitic schist hostrocks range from three to ten metres in thickness and the tectono-clasts of vein quartz are erratically distributed within the unit. There is little record in the literature regarding the grade of the various mineralized showings at the Millie Mack. In 1981, an assay on samples from a 2.83-tonne shipment of mill concentrate from the Millie Mack was 12.8 grams per tonne gold, 768 grams per tonne silver, 0.16 per cent copper, 2.5 per cent lead, 3.0 per cent zinc and 3.9 per cent arsenic (Assessment Report 9965, Paper 1986-1). More recently, in 1989, the results from seven percussion-drill holes were reported in the George Cross News Letter (number 178, 1989), with the highest assay being 3.5 grams per tonne gold and 419 grams per tonne silver across 3.05 metres in drillhole 89-15.
There are potential reserves of 1,542,070 tonnes grading 4.79 grams per tonne gold and 222.82 grams per tonne silver (George Cross News Letter 01/05/89).
Recently it was reported that the Millie Mack property contains a large graphitic shear zone consisting of a mixture of extremely fine particles of 70 per cent minus 400 mesh graphitic sericite, sericite and silica. This graphitic shear zone contains 8,889,580 tonnes of which about 1,814,200 tonnes are deemed open pittable (George Cross News Letter No.95 (May 17), 1995). Micro Minerals Resources Inc. worked the property in 1995.
For a good work history see NMI entry 82K/4 Au1 and Assessment Report 9965.