University of Nevada, Las Vegas

Goldfield Mascot Mining Company p 12

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States, even the far-famed Cripple Creek, Colorado, and comparable only to those of one mine in Westralia. Of course, this rich ore has led to much of what is euphemistically termed "high-grading," in common language, ore stealing, in spite of which, however, both mine owners and lessees are making great profits. For example, in the celebrated Mohawk mine a total gross production of $5,000,000 was made in 106 days, and the average assay value of all the ore shipped, to November 20, 1906 ($9,664,000), was $117.10 per ton.The question of the depth to which payable values will be found in the veins is still undetermined, but the fact of an increase in copper sulphides and in tellurides as depth is increased indicates that these veins will carry payable ore as deep as mechanical appliances can work to advantage.The width of the payable ore bodies in the veins vary greatly. The extremes may be placed at two feet and thirty feet, though in places the widths expand to no less than 100 feet. The lengths of the ore bodies also vary in the different veins. The longest known to the writer is 350 feet.The veins are numerous but irregular, both in course and character. There is, however, a general likeness observed in all those of any one belt or zone.FLAT VEINS AND MERGERSBesides the veins having a dip varying from vertical to, say, 60 degrees from the horizontal, there has recently been discovered a most important series of great extent having a dip varying from 45 to 27 degrees from the horizontal. These latter or flat veins contain the greatest ore bodies and appear to be formed at the contact of two flows of igneous rocks, thus being in the nature of bedded contact veins. The significance of these low-dipping veins when considered in the light of apex litigation becomes very great, and has led to the inaugura-13




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