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W,,--ITASCA: <br /> Denver, Inc. <br /> is the Cripple Creek Breccia, which comprises clasts of phonolite, granite, granitic gneiss, latite, <br /> and syenite within a variable groundmass. <br /> The breccia is vuggy in areas as a result of hydrothermal alteration, which has resulted in <br /> alteration of mafic minerals to carbonate and low-grade potassic, argillic, sericitic, and pyritic <br /> alteration (Eary et al. 2003). Various stages of mineralization have been recognized and <br /> documented in the district,with the proportions of each stage varying between and within veins, <br /> but the ore mineralogy is consistent throughout the system (Thompson et al. 1985). Gold occurs <br /> as calaverite, sylvanite, and as disseminated native gold generally associated with pyrite. <br /> Pyrite is the primary sulfide mineral throughout the deposit. Small amounts of other sulfide <br /> minerals (i.e., galena, sphalerite, marcasite, molybdenite, tetrahedrite, stibnite, pyrrhotite, and <br /> chalcopyrite) have been documented but are rarely encountered in current exploration drilling <br /> (Eary et al. 2003). Gangue minerals include quartz, dolomite,fluorite, calcite, gypsum, anhydrite, <br /> celestite, rhodochrosite, magnetite, apatite, and manganese and titanium oxides. Calcite and <br /> dolomite are the most common carbonate minerals throughout the diatreme and occur as <br /> disseminations, veinlets, and veins that reportedly increase in frequency and abundance with <br /> depth. Near the surface, the carbonates are typically absent and pyrite-alteration products are <br /> present, including goethite, jarosite, iron oxyhodroxides, gypsum, barite, celestite, manganese <br /> oxyhydroxides, and clays (Eary et al. 2003). <br /> 3 <br />