There are a number of mineralizing styles and models in the Republic/Greenwood Districts:
1) Gold and Copper-Gold Skarns: Fe-Cu massive sulfide/oxide horizon in Brooklyn Fm. Present in all major “skarn” deposits in the district. Examples are Phoenix, Motherlode and Crown Jewel (“Buckhorn Mtn”).
2) Mesothermal Quartz Veins with Gold (+/- Ag, Pb, Zn). Examples are Providence Mine, Dentonia, Camp McKinney, May Mac. Polymetallic silver-lead-zinc veins with lesser gold.
3) Epithermal Quartz Veins commonly in the Republic District and often marked by the paleosurface between the Eocene Marron and Kettle River Formations and the overlying Oligocene Klondike. Examples are Mountain Formation Knob Hill Mine, Emanuel Creek, Union Mine and Picture Rock Quarry.
4) Cretaceous – Jurassic Alkalic Intrusives with Cu-Au-Ag (+/- PGE’s) with a strong spatial association between these intrusives and Jurassic thrust faults. Examples are Lexington-Lone Star alkalic porphyry type mineralization, Franklin Camp, Sappho cpy rich shears with PGE’s and Au, Golden Crown, Wildrose and Rossland type veins close spaced, parallel, en-echelon veins of gold in massive pyrrhotite-pyrite-chalcopyrite veins & quartz veins.
5) Gold Mineralization Associated with Serpentinite related to #3, #4 because an association with structure = an association with serpentinite. Known bodies of mineralization have traditionally been small, but often high grade. Examples are Athelstan – Jackpot - gold in ........

Lexington-Grenoble.
Access to the mine will be via the existing three surface portals, drifts and ramp.

The proposed mining method is jackleg/stoper pilot raise and slash. The overall mine sequence will generally be mined from the top down. A typical stope layout is shown in Figure 16-4 which will average 3 m thick and dip at +30 degrees. Initially a 2.4 m by 2.4 m pilot raise will be driven, in ore, from the lower sublevel transport drift to the upper sublevel overcut drift, at a central location along the stope strike. A three-drum slusher cut-out will be excavated at the base of the pilot raise in the operator accessway.

Open stope jackleg/stopper slashing will start at the base of the pilot raise, slashing outward along strike to the stope pillar locations on either side of the stope, and upward along the dip of the deposit body to the overcut drift. Drill steel will be 29 mm diameter and up to 2.4 m in length. The powder factor is estimated to be 0.50 kg per tonne. Open stope slashing will proceed outwards and upwards from the pilot raise. Access to the stope face will be via the sublevel overcut drift and pilot raise. A nipping slide and stope access ladders will be installed in the pilot raise. Blasted mineralization will be slushed down to the sublevel transport drift where it will be picked up by 2.5 and/or 3.5 cubic yard load/haul/dump/machines. These machines will not be able to access broken mineralization in the stope, from the lower s ........

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