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Diamond Valley Gold Mining Company Report page 2

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That portion of the Goldfield District which has thus far proved the most productive contains theproperties in the vicinity of the Goldfield Consolidated Mines Co. These properties are shown on the plan map herewith and occupy the southern end of a mineral region or belt which extends from theFlorence northerly a distance of some 2 1/2 miles to a point about 1500 feet north of the Conquerorshaft and occupies,in general,the valley between Vindicator and Columbia Mts.,its western boundary beingthe surface trace or outcrop of a fissure known as the Columbia Mountain Fault. This fault is traceableon the surfacefor some two miles in length(shown on the map) disappearing south of Columbia Mt.under the dacite formation which there overlies the fault covering it to a depth of some 250 feet. This fault dips to the east on a slight but varyingangle,having a general dip of of about 28. As, exposed in the Conqueror workings its dip is about 25; in the Consolidated the general dip is about 28. In the vicinity of the Florence it breaks sharply to the eastand here has a very steep dip to the east. A short distance south of the Florence the fault ends in a sharp break to the east.This fault forms the connection with the regions of mineral origin for this portion of the district,anddevelopments of the Consolidated, Jumbo Ex.,Merger,and Atlanta properties show it to be the main channelthrough which the mineralizing solutions have arisen,branching there-from upward into the formations abovethrough connecting fissures. This channel,rather than a plane,is a broken or crushed zone of con-siderablethickness and somewhat uneven,some of its irregularities probably being due to breaks subsequent to theoriginal faulting. The formations lying above this zone,being affected by movement along the zone subsequent to the original break have been fractured by irregular fissures extending down to and merging with thismain zone or channel,and in these fissures,as well as in the zone,the rising solutions have deposited verylarge and rich ore bodies.So far as development shows there is no particular preference of the ore for any of the geological formations.In the Consolidated it has been found in the dacite,latite,and shale;and in the Florence in the dacite and andesite,the richest and largest bodies of the latter being in the andesite. In the Jumbo Extension,at last accounts,the ledge after having been followed for some distance along the latite shale contact is found to be penetrating the shale with a good grade of ore. This late development is especially encouraging for the district as it demonstrates the persistence of the ore with depth,and that ore may be found in any of the formations. The determining factors are the physical conditions of fracture and channels for circulationof the mineralizing solutions rather than any particular kind of rock and these conditions have been principallydetermined by the Columbia Mountain fault and connected movements for this region or belt.In the workings of the Conqueror Co. to the north of the Diamond Valley Co's. property,in the broken materialof the fault itself ore of value of some $30 per ton has been obtained over a considerable distance,showing that the mineralizing solutions have extended along this fault zone at least this far to the north. Sufficientdepth has not yet been attained to determine whether or not there are good bodies of ore on this property.Section"A" herewith shows the above conditions existing in the Consolidated and Merger properties. The Merger shaftat a depth of between 1700 and 1800 feet passed through a wide zone of broken and crushed material,with graniteshowing at the bottom. This,doubtless,is the main fissure,and practically coincides with the positionpredicted for it by the disclosures west of the Merger shaft as shown on the section. On the 1750 level workingshave been run into the Atlanta ground,opening up ore which is without doubt connected with this main fissure.Ore is now being shipped from this point and according to official statements of the Company is continuing toimprove.