CENTEAL AI^D EASTEEN NEVADA. 353 



composed, forming a soft belt, one or two feet in thickness, that may be easily- 

 removed with a pick. In other places the vein is filled with a compact body 

 of white quartz, either with or without ore, inclosed by hard, unaltered granite 

 walls and accompanied by only a thin seam of clay. The width of the vein 

 varies from two feet, and sometimes more, to a mere seam, expanding and 

 contracting irregularly. In places it maintains an average width of 10 or 12 

 inches for a considerable distance, sometimes hundreds of feet, then narrowing 

 so that the walls come almost together, leaving only a seam, that cannot be 

 traced without difficulty. Not unfrequently the vein shows a width of four 

 feet between its walls but consisting of two seams of quartz, between which is 

 a mass of softened granite rock. This " horse," if such it may be termed, re- 

 sembles generally the inclosing rock of the vein, but often has a banded or 

 stratified appearance. It maintains itself, with varying width, for long dis- 

 tances, pinching out finally, the quartz-seams reuniting or, perhaps, being lost 

 altogether by a contraction of the two walls, or by a division of the main fis- 

 sure into numerous ill-defined seams and branches. The ore, as exposed in 

 the drifts and stopes, usually appears in a pay-streak, an inch or two in width, 

 now and then expanding to six inches, and in rare instances to twelve or 

 eighteen. Thus, in the Buel mine, in one of the finest, if not altogether the 

 best body of ore ever developed on Lander Hill, the pay-seam, consisting of 

 ore worth $300 or $400 per ton, had a width of 18 or 20 inches, maintaining, 

 for a length of over 100 feet, an average width of 12 or 15 inches. The ore 

 consists of quartz, carrying more or less galena, copper pyrites, iron pyrites, 

 and some zincblende, with a rich distribution of stephanite, pyrargyrite or ruby 

 silver, polybasite, and fahlerz. Manganese spar is a characteristic associate of 

 the gangue. Crystallized calcspar occurs with crystallized quartz in cavities. 

 The veins of ore generally present a beautifully banded structure, the various 

 minerals above named being arranged in parallel layers, indicating the order 

 in which they were successively deposited on the side of the fissure. 



The mode of occurrence of the ore in the vein appears to be in distinct 

 bodies, which vary in size from mere pockets, or small bunches, to large de- 

 posits, 100 or 200 feet in length and depth. Large portions of the vein, 

 even where possessing considerable width, are barren, or contain ore so 

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