The McMillan deposit is in the southern portion of the Logan Mountains, 65 km NE of Watson Lake. It is also referred to as the Quartz Lake deposit. Rocks hosting the deposit consist of argillite, sandstone, limestone and massive sulphides. Mineralization includes concordant and discordant types. Concordant mineralization mainly consists of beds of massive sulphides with sphalerite, galena and carbonate (siderite?) with minor sulphosalts. Discordant mineralization is widespread and consists of veins and veinlets that cut layering and cleavage. Quartz-siderite is the most common vein filling. Most stratabound deposits in Selwyn Basin are attributed to syngenetic origins. However, deposits similar in mineralogy and geologic setting to the McMillan deposit are thought to be of a replacement type origin. Two models are proposed for the origin of the McMillan deposit:: a) mineralization was hydrothermally introduced into a carbonate-rich post depositional sequence and selected limestone beds were replaced by sulphides and siderite, or b) the mineralization was hydrothermally introduced onto a seafloor and sulphides and siderite were precipitated as lateral facies equivalents of limestone.

The Marg deposit consists of four stacked massive sulphide lenses hosted by Devono-Mississippian felsic metavolcanic rocks. Based on 1988 and 1989 diamond drilling, reserves are estimated 2.86 million tonnes grading 1.62% Cu, 2.25% Pb, 4.17% Zn, 55.9 g/t Ag and 0.89 g/t Au.

The Mel deposit consists of a concordant, folded lens of barite and coarse recrystallized galena and sphalerite at the contact between Cambro-Ordovician limestone and shaly limestone. Based on diamond drilling since 1972, the deposit contains geological reserves of 6,200,000 tons grading 6.77% Zn, 1.92% Pb and 49.6% barite to a depth of 457 m. The mineralization is open to depth and the higher grade part of the deposit lies below 305 m.

The past-producing McKay Hill property on NTS map sheet 106D/6 (Nash Creek) has previously been described as polymetallic Ag-Pb-Zn ± Au-style mineralization. During the 2009 YMIP-funded exploration program the central claims on the property were mapped and numerous distinct differences from the proposed polymetallic model became apparent. Unlike Keno Hill, veins on the McKay Hill property lack siderite gangue and are not present as vein-faults. Propylitic alteration halos surrounding vertically zoned ore shoots (high-level Au-Cu and deeper level Ag-Cu-Pb) were observed within consistently north-northwest-striking, near vertical, siliciclastic and hypabyssal-volcanic rocks. The Ag-Pb-Zn veins in the Keno Hill Camp were emplaced in discrete dilational fault structures within polydeformed clastic metasediments and are not associated with extensive alteration. Host rock competency in both areas is vital in controlling mineralization. Re-evaluating the regional framework could potentially illustrate the area’s metallogenic potential for different types of mineral occurrences.

Sphalerite and tetrahedrite occur with arsenopyrite and minor chalcopyrite and galena in a tabular, fault-bounded body which cuts granitic rocks of the Cassiar batholith. Diamond drilling between 1986 and 1988 outlined a deposit 1100 m long and 50-100 m wide containing geological reserves of 12.3 million tonnes grading 6.17% Zn and 26 g/t Ag. These reserves are amenable to open pit mining and the deposit is open to depth.

The Brown McDade Mine is a gold-silver discovery in Yukon, halfway between Whitehorse and Dawson. It lies in the area unglaciated during the Pleistocene Period. Diamond drilling and stripping in 1946 indicated commercial values across a width of 10 feet and over a length of 1000 ft. The geologic structure is that of a Late Tertiary, dike-like body of quartz feldspar porphyry cutting quartz diorite of Jurassic or later age. This body has a Northwest strike and dips steeply west. The ore zone lies in the porphyry and is believed genetically related to it. The mineralization consists of a cherry-like fine grained blue quartz, with disseminated sulphides comprising less than 5% of the mass. Metallic minerals are pyrite, arsenopyrite, and sphalerite, with lesser amounts of galena, chalcopyrite, tetrahedrite, stibnite, bournonite, jamesonite and gold. The gold is associated with the pyrite in fine particles, the majority less than 150 microns in size. The gold-silver ratio is about one to ten. Sericitization and carbonatization are the chief forms of hydrothermal alteration, while considerable limonite, and around the ore zone, jarosite, have been produced by weathering. On the basis of comparisons with known deposits, the Brown McDade is considered to belong to the deeper epithermal type. It should continue to reasonable depths although the ore shoots are likely to be erratic. The area south of the main ore zone, underlain by schistose rocks will probably be unfavorable for the occurrence of ore. A copy of this thesis is available at the EMR library – QE376.5.Y8 L35. This thesis is available online at https://open.library.ubc.ca/cIRcle/collections/ubctheses/831/items/1.0053530.

The Dromedary property consists of 344 claims on Dromedary Mountain, Kalzas Mountain, and the intervening Macmillan River valley, all immediately northeast of Tintina Trench and 240 km northeast of Whitehorse. The property lies within Selwyn Basin geological terrane, and the following rock units are present: Proterozoic-Cambrian Hyland Group, Kechika phyllite and limestone, minor Road River shale and siltstone, Earn Group conglomerate, limestone, black silty shale and baritic chert, and overlying Permian shelf sediments. South Fork subvolcanic intrusions and Cretaceous granitic plugs have induced local biotite and calc-silicate hornfels and skarn. The area was staked by Anaconda in 1980 and four areas of interest identified: Dromedary Creek, Dromedary Mountain, François and Kal-Cave. Blackstone Resources Inc. optioned the property in 1996 and has drilled the Dromedary Creek and François areas, encountering massive sulphide mineralization in all five holes. Economic grade Pb-Zn and massive pyrrhotite with significant gold occur on the François grid. In 1997 the magnetic signature of the pyrrhotite on the François grid was traced 5 km, and soil anomalies were detected further to the west. In the Kal-Cave area a 7.5 km long lead-zinc soil anomaly was refined and numerous new occurrences of iron-sulphide mineralization, carbonate porphyroblasts, manganese and iron oxide were detected. Best samples from this area contain 5.53% Pb and 5.83% Zn.

Mineralized zones on the Jason property are stratifrom, sediment hosed Pb-Zn-barite deposits that occur in a Late Devonian age marine carbonaceous shale and turbidite sequence. The Jason Property is located 400 km northeast of Whitehorse near Macmillan Pass on the Canol Road. Since the discovery of mineralization in 1975, eighty-nine diamond drill holes have delineated three mineral deposits. In order of their discovery, they are known as the Main, South and End zones. Geological reserves indicated and inferred for the three zones total 14.1 million tonnes averaging 7.1% Pb, 6.6% Zn and 79.9 g/t Ag. The following questions are the focus of the study:: 1) What is the stratigraphic position and setting of the South zone? 2) What is the geological relationship of the South zone to the Main zone? 3) What is the geometry of the South zone? 4) How can the mineralization in the South zone be described in terms of mineralogical and textural facies? 5) What constraints on the processes of ore formation can be demonstrated by utilizing the above studies?

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Kalzas, in central Yukon, is a porphyry-style stockwork and sheeted-vein wolframite deposit. Alteration includes a potassic core, a quartz-tourmaline-sericite zone and an outer quartz-sericite-pyrite zone, the latter in excess of 2 km in diameter. Wolframite is confined to the inner two zones, in an oval area 1500 m by 800 m. The wolframite is disseminated within the quartz-tourmaline stockwork and also occurs as coarse crystals in sheeted veins. Mineralization occurs within Neoproterozoic to Early Cambrian Hyland Group quartzites and phyllites, which are likely intruded at depth by a pluton, possibly of the Cretaceous Tombstone Suite. From 1981 to 1984, Union Carbide carried out mapping, soil and rock geochemistry, an airborne magnetometer survey, road building, trenching and drilling of two diamond drill holes. Results from Copper Ridge's 2001 sample program range from 0.3% WO3 to 0.5% WO3 over widths up to 70 m. They demonstrate the potential to define a signifi cant resource of surface-mineable tungsten mineralization at a grade of 0.4% WO3 or better. Drilling is required to confirm grade continuity at depth and along strike.