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-- T-4515 70 <br />to obtain an analysis for each sulfosalt mineral seen during petrographic study. However, <br />many sulfosalts aze virtually indistinguishable under the microscope; undoubtedly, some <br />minor, fine-grained species were missed. Polybasite, utaninite, chlorazgyrite, stephanite, <br />gersdorffite, jalpaite, and pearcite have also been reported in the district (Wright, 1954; <br />Moore et al., 1957; Francis, 1987; Hennigh, unpub. data) but were not found in this study. <br />The dolomite stage of mineralization consists solely of 1- to 3-mm rhombohcdral <br />crystals of dolomite which are locally pale green or pink in color due to a significant <br />amount of manganese in the crystal structure (J. Humphrey, pers. comm.). Dolomio: <br />sometimes occurs as open space fillings in quartz-sulfide veins, but normally crosscuts, <br />offsets, or cements breccias of the eazlier sulfide mineralization. <br />Superpene Stage <br />Neaz the surface and in veins through which groundwater passes, chalcopytite <br />and, less frequently, galena and sphalerite, are replaced by covellite, chalcocite, and <br />digenite encroaching from fractures and grain boundaries (Fig. 44). covellite, the most <br />abundant oxidation product, occurs as both regular and blaubleibender covellite (Leonazd, <br />r <br />pers. comm. Chalcocite sometimes occurs between an unoxidized base-metal sulfide and <br />covellite (Fig. 44a). Chalcocite also occurs as an irregular intergrowth with (Fig. 446) or <br />as parallel lamellae in digenite. The latter texture was formed by exsoludon along (111) <br />cleavage (Ramdohr, 1980). Digenite also occurs without chalcocite. Malachite, azLUite, <br />and native silver rim minerals completely altered to secondary copper minerals (Fig. 446). <br />