![]() The veins are of variable size (up to 2 m thick), variable orientation, and occur in dilatant zones throughout the camp. Pegmatite-Type Veins: coarse-grained potassium feldspar, biotite, epidote, and calcite (±albite, apatite, garnet, and quartz) these veins are distinctive and occur with or without sulphide minerals. These veins are not abundant in the Pit 3 area, but are significant in Pit 2 and comprise much of the ore within areas north of Pit 2 and east of Ingerbelle. Magnetite Veins: with or without copper sulphide minerals, of variable size from fine fracture filling, to vein stockworks, to sheeted vein swarms, to 3-m to 4-m thick veins. Numerous veins, vein envelopes, and fracture-filling mineral assemblages crosscut, or occur within both potassic, and to a lesser extent, albitic alteration, and are described below. Potassic alteration appears to be spatially associated with certain phases (LH2) of the LHIC. Potassium alteration typically produces rocks with a faint to strong orange or pink colour, which is enhanced with weathering, suggesting that the alteration contains an ultra-fine dusting of hematite. In areas peripheral to the sodic alteration, potassic alteration is pervasive, either flooding the rock matrix with fine-grained potassium feldspar or replacing primary plagioclase with potassium feldspar, and ferro-magnesium minerals with biotite, epidote, calcite, chlorite, and magnetite. Where potassic alteration overprints the sodic alteration, it is almost exclusively as fracture fill and veins. ![]() Potassic alteration occurs as veins and fracture fill (K-feldspar and biotite), or as pervasive K-feldspar flooding of the rock matrix. ![]() Much of the sodic alteration appears to be early and pre-mineralization however, there also appears to be a more confined, later phase of sodic alteration with a high pyrite-tochalcopyrite ratio that occurs on the northern and southeastern sides of Pit 1, which may be associated with small cylindrical intrusions. A wide band of intense sodic- metasomatism cuts across the mine area in a northwest–southeast direction, extending from the north side of the Ingerbelle deposit and across the Similkameen River canyon, through the south side of Pit 2 and the north sides of Pit 1 and Pit 3. This process results in bleaching of the original rock and a reduction in grain size, forming a pale-gray or greenish-gray, very competent rock. In addition to albitization of feldspars and conversion of ferro-magnesium minerals to epidote (± diopside and chlorite), magnetite and opaque minerals are destroyed. Pervasive sodic alteration occurs as a texturally destructive albite-diopsideepidote metasomatism. Sodic alteration is commonly pervasive (sodic metasomatism), but can also occur as fracture- controlled veins or vein-stockworks. Three main types of alteration have been defined-hornfels, sodic, and potassic each has its own spatial and temporal distribution. ![]() Each mineralization type can be found in all pit areas, but each pit is unique with respect to the relative quantities and character of mineralization type.īoth mineralization and alteration demonstrate a zonation through the camp, though not in a manner typically associated with calc-alkaline porphyry deposits. Mineralization had been subdivided into four types, as follows: 1) disseminated and stockwork chalcopyrite, bornite, chalcocite, and pyrite in altered Nicola and LHIC rocks 2) hematite-magnetite-chalcopyrite replacements and/or veins 3) bornite-chalcopyrite associated with pegmatite-like veins (coarse masses of orthoclase, calcite, and biotite) and 4) chalcopyrite-bearing magnetite breccias. Although there are several areas that have been mined separately over time, both alteration and lower-grade mineralization occurs between these areas, and all mineralization is thought to be part of a large, single system.Īs a generalization, mineralization at Copper Mountain consists of structurally controlled, multidirectional veins and vein stockworks, with peripheral disseminations. Mineralization at Copper Mountain is classified as an alkalic porphyry deposit.
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