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$PURR MONOGRAPH "Contact" in the Mollie Gibson, p. 181. The "contact," where most development in the Mollie Gibson mine has occurred, is the Silver fault, which separates the Leadville dolomite [Red Cliff] from the Weber [Belden].8 It is marked by thick breccia containing fragments of blue lime [actually Red Cliff Dolomite(?)] and occasionally ore. Emma fault, Clark fault, pp. 161-183. On the 7th level, 220 ft. north of the Gibson fault, is the Emma fault, part of the Della fault system. The fault strikes east- west, dipping south at about 30°. It is probably same fault that cuts the 4th level of the Smuggler mine. There is evidence of a fault nearly parallel with the Silver [breccia I S II] and only a short distance from it; this fault, found throughout the Mollie Gibson and the Smuggler, displaces the original ore bodies that formed after development of the Della system (east-west, southerly-dipping) faults. It is known as the Clark fault. This fault, trending north-south and nearly vertical, offsets rich ore deposits along the Gibson fault-Silver fault intersection (and up-dip along the Gibson to the north), down and to the north into the Smuggler, where nearly identical ore is found along the Smuggler fault-Silver fault intersection and north along the Silver. Thus Spurr concludes that the Gibson and Smuggler faults are actually the same and are also displaced by the Clark fault. Likewise, the Emma fault is possibly the same as the Della which is not present in this section. Nature of ore in Mollie Gibson, pp. 184-185. Ore occurs on the Gibson fault, with dolomite below and shale above, most of it actually in the shale [Belden]. This ore is very rich, with large amounts of polybasite [Ag16SbiS11; actually mostly pearceite] and native silver. Silver occurs mostly below the polybasite and appears to be secondary. Above the polybasite shoot, silver becomes less and lead and zinc increase, especially ° Virtually all citations prior to the 1979 BRYANT REPORT, Part IV post 63, refer to the sequence of carbonaceous shales and limestones immediately overlying the Leadville Limestone as the "Weber Formation" or "weber Shale" for exposures in Weber Canyon, Utah, with which these rocks were miscorrelated. Proper correlation with the Belden Shale at its type locality on the northeast side of the Eagle basin was initially recognized in 1944, BRYANT REPORT 23, but this correlation has been only gradually corrected. In this Bibliography, where the author used the term "weber" it is so given, followed in brackets by "Belden," e.g., "Base metal ores found in the breccia at the bottom of the Weber [Belden] constitute the milling ores of the district." Bruce A. Collins - 3 - BieLtocRAPxx