CENTEAL AND EASTEEK NEVADA. 



419 



This material rarely penetrates more than two or three feet into the 

 overlying formation. Within this distance the shale is split up and inter- 

 stratified with quartz and calcite seams. 



Explorations made in this material have developed several chambers of 

 rich ore lying in the limestone below, and a number of mines have been lo- 

 cated along the contact of the two formations. The Hidden Treasure is the 

 best example of this class of deposits and one that has furnished a great deal 

 of rich ore. The deposits of ore occurring in beds and chambers upon 

 Bromide, Chloride, and Pogonip Flats are exceedingly irregular in size and 

 shape; sometimes they are found filling depressions in the rock, at others 

 lying between well-marked beds of stratified limestone ; again they are de- 

 posited upon beds or floors and penetrate the inclosing limestone, either above 

 or below. 



Intimately connected with the beds are the vertical and oblique chan- 

 nels of ore ; these vary in width from a few inches to several feet. They 

 are generally connected with the beds or chambers, and branch out from 

 them, frequently extending from one bed of limestone through to the next 

 one below, many of them connecting beds of rich ore. Frequently these 

 channels extend from the principal deposits for a considerable distance, and 

 then terminate abruptly ; occasionally they are quite wide, and maintain a con- 

 tinuous course for a long distance. 



Whatever the occurrence of the difierent bodies of ore on Treasure Hill 

 may be, the characteristic mineral composition of the material is the same 

 under all conditions, and similar to that of the Eberhardt mine and contact 

 deposits, already described, varying only in the richness of the ore, in chlo- 

 ride of silver, and the amount of the accompanying base metals. 



Observations upon the position and occurrence of the ore-bearing bodies 

 seem to indicate that they must all have had a similaf origin, and have been 

 filled from the same common source of supply. Judging from the develop- 

 ments thus far carried on it seems highly probable that the Eberhardt fissure 

 has served as one of the principal sources for the supply of ore scattered over 

 the hill. The ore in the main channel finding cracks and seams in the lime- 

 stone may have extended laterally until, meeting the vertical and obhque 

 cracks, it has been forced upward, penetrating wherever the rock afforded any 



