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CC&V GOLD MNG. CO. ID:'19-689-254 fEB 02'94 23:15 No .026 P.14
<br />i ~ Table 1. Examples of of oro tleposits in or near the Colorado Mineral Belt, and their
<br />goofogic characteristics. Minerals listed in order of decreasing abundance. Data from
<br />references tired in text Mineral abbtcviadons: py-pyrite: mc-taarcasiu: en-txrarglte; cov- .
<br />covelliu:cpy-chaicopytiu; gaquatu S-narive salfur, td-tetrahedriu;hat-barite:sl-
<br />sphttlerite;gn-galena; Ag-native silver, Garb-misc. carbonates (including calcite, dolomi[c, or
<br />rhodochrosite); edul-adularia; tell-tellurides (including Au-tellurides); fluor-fluorite; W-
<br />tungsten minerals; tnply-molybdenite.
<br />•
<br />T • Deacri tlon Miaeralo Noat rock Alteration Elements
<br />Acld•aalfate DLtamotneted Py, mc, cn, Voluniu esuaaive altxraaea Cu, Au,
<br />eplthermal wltldet In latettsely cov, cpy, qts, to silica, alunite, Ag, As,
<br /> acid-alwed wlcanic
<br />cauea S, td, bar ksolinite, clays Zn, Pb
<br />Porp6~ry Disseminated, vein, Centrtd moly, lgnoow S' ieitiration Mo. lesser
<br />Motybdennm and stackwork otrs q¢, !loot. lntntslves & Cu do F
<br /> avociatad with Distal py, tl, saawadiag
<br /> i us intrasions n garbs rode
<br />Igneous Veins, disseminated Py, sl, gn, Igneous Scriciti~uaa, dtt, Pb,
<br />Yolymetaltic orq in i/,neaa7 host e¢:tarbs,tW latNftvei: slllclflcatltM Cu. AQ,
<br /> rode volraniu Au
<br />Adalarla- Veins in wleanie Sl, Qn, py, Ash-ilov tuffs, SilieiGcauion. Zn, Pb,
<br />frriritr host m-Pt rpy, nit. Ag, otbr Altsmtion t0 Cu. Ag,
<br />eplthermal wrbs,q¢, voltmtlc catbottatas,Gays Au
<br /> adul.6ar toclQ
<br />Central Clty Qusr¢.salfido vents Central py, Maaetdimenu Saioitiastion, Zn, Pb,
<br />• tTpe Inmetasedlments q¢.Inut¢siag silicification Ca.A;,
<br /> sl, go, cpy, Au
<br /> q¢, Garbs
<br /> htYall
<br />High•sulfide Sulllde•rich veins, Py, sl, cpy, Limeuone. Sulfitk repltitemmt Zn, Pb.
<br />carbonate- rq>faamrnt gn, d, qtz, dolomite, ofcarbonatw; Cu. Ag,
<br />hosted depositt in catb asndttette, silieifiution Au
<br /> m n tacks shale
<br />Gaid• Gald•tellurldeveau u:ll, bar, Alkalle igneous Silicification Te, F, Au,
<br />telluride asaorioicdwith fluar,cubr, nxkt catbortete,
<br /> alkalis igneous sulfates, Metaudimrnia sulfate
<br /> actlvl mirux
<br />Sharmsa• SulGdwn:plaeiug Lowwnod. Limr:ataie, Silicificauon ,Zti, Pb,
<br />type andtlllingopen mlfido:bu, dolomite! A6
<br />carbonate- spaces in c.abtmaze crab, sL gn, silieifieatitm
<br />hosted rarJcr low 'to
<br />METAL.pIi CI.ASSIFICATIOPI SCLiEME
<br />The results of the study to date confitTn [hat not all mine drainage is acidic and that ntine-
<br />drainage waters need not be acidic to carry high concentrations of dissolved metals. Due to the
<br />broad range in pH (from less than 2 co neaz 8) and dissolved metal concenvations (6-7 orders
<br />of magnitude) measurctl, we have found it convenient to classify drainage compositions
<br />according to pH and the sum of dissolved base metals Zn, G11, Cd, Pb, Co, and Ni (Figtae 2
<br />and!'icklirt ei al„ 1992x. These base nxtals arc of significant cnncem environmentally, and
<br />arc the doarinant heavy metals prescm in nearly all drainages rumpled. We have established
<br />nine different classes of metal-pH values that are based on general groupings of [he data
<br />(Figure 2 and Ficklin et al., 1992, Plumlee et al., 1992). Boundaries between these classes
<br />have not been defined ort a geochemicatly-rigorous basis. Concentrations of the bate metals
<br />LJ
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