The Project comprises 173 contiguous mineral claims covering a combined area of 219,256.7 hectares, and held 100% by the Aston Bay/American West Joint Venture.
American West and Aston Bay will form an 80/20 unincorporated joint venture and enter into a joint venture agreement. Under such agreement, Aston Bay shall have a free carried interest until American West has made a decision to mine upon completion of a bankable feasibility study, meaning American West will be solely responsible for funding the joint venture until such decision is made.
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Summary:
The Storm Copper Project lies within the Cornwallis Lead-Zinc District, which hosts the past producing Polaris Zn-Pb mine on Little Cornwallis Island. The Project covers a portion of the Cornwallis Fold and Thrust Belt, which affected sediments of the Arctic Platform deposited on a stable, passive continental margin that existed from Late Proterozoic to Late Silurian. Southward compression during the Ellesmerian Orogeny (Late Devonian to Early Carboniferous) produced a fold and thrust belt north and west of the former continental margin, effectively ending carbonate sedimentation throughout the region. This tectonic event is believed to have generated the ore-bearing fluids responsible for Zn-Pb deposits in the region.
Storm Copper is interpreted to be a sediment-hosted stratiform copper sulphide deposit, broadly comparable to Kupferschiefer and Kipushi type deposits. Storm comprises a collection of copper deposits (Cyclone, Chinook, Corona, Cirrus, Thunder, and Lightning Ridge) and other prospects and showings (including the Gap, Squall and Hailstorm prospects), surrounding a Central Graben structure. The Central Graben locally juxtaposes the conformable Late Ordovician to Early Silurian Allen Bay Formation, the Silurian Cape Storm Formation, and the Silurian Douro Formation, and was likely a principal control on migration of mineralising fluids. The Storm Copper deposits are hosted mainly within the upper 80 meters of the Allen Bay Formation and to a lesser extent in the basal Cape Storm Formation.
The Allen Bay formation includes three geological members, which are discretely logged and modelled along with the Cape Storm and Douro Formations. Starting immediately below the Cape Storm Formation is an alternating dolomicrite and dolowackestone unit (“ADMW”), a brown dolopackstone and dolofloatstone unit (“BPF”), and a lower varied stromatoporoid unit (“VSM”). Copper mineralisation is generally hosted within the 35 to 50-metre thick ADMW and approximately 35m thick BPF units. The Storm Copper sulphide mineralisation is most commonly hosted within structurally prepared ground, infilling fractures, and a variety of breccias including crackle breccias, and lesser in-situ replacement and dissolution breccias, with a relatively impermeable “cap” of dolomicrite of the Silurian Cape Storm Formation.
Mineralisation at Storm Copper is dominated by chalcocite, with lesser bornite and chalcopyrite, and accessory cuprite, covellite, azurite, malachite, and native copper. Sulphides are hosted within porous, fossiliferous units and are typically disseminated, void-filling and net-textured as replacement of the host rock. Crackle, solution and fault breccias on the decametric to metric scale represent ground preparation at sites of copper deposition. Sparse vertically plumbed structures have higher grades and dominate the mineralisation geometry at deposits such as Chinook and Lightning Ridge. The Cyclone deposit has more typical stratigraphic control; the ore bodies are flat lying where mineralisation has permeated further into the subhorizontal structurally prepared Allen Bay Formation strata. The Corona and Thunder deposits display some structural control to mineralisation amongst sub-horizontal bodies and are interpreted as a mix of the two mineralisation styles.