THE OEE DEPOSITS. 75 



rections. They are sometimes round, and again tabular, and are found with 

 and without ramifications. There are pear-shaped deposits and pipes round 

 and flat, irregular and symmetrical. A common form is that of a bent sau- 

 sage somewhat flattened, and both ends downward. In fact, the form of the 

 deposit has been governed by the permeability of the rock. Although these 

 deposits are of all shapes and sizes, taken as a whole they have a down- 

 ward trend; that is to say, they extend farther in depth than they do lat- 

 erally. Some are found lying nearly flat, like bed veins, but this manner of 

 occurrence can usually be accounted for by the hardness and insolubility 

 of the underlying rock. The ore bodies at first sight often seem to have 

 no connection with any fissure or channel through which they could have 

 been filled, but such a connection has been demonstrated in so great a 

 number of cases that it may be presumed to have existed in all. 



In by far the greater number of instances this fissure has led to the 

 discovery of the ore body, or its existence has been shown in the workings 

 subsequent to the discovery. In some it has been closed by pressure, in 

 others it has not been revealed by the explorations of the miner, who natu- 

 rally does not think it necessary to follow every small crevice or opening 

 which he may encounter. This connection of ore bodies with fissures is a 

 very important one, as it throws a great deal of light upon the nature of the 

 deposits, and although the fissure may apparently be very insignificant and 

 nothing more than a seam in the rock, the crushing and rending of the lime- 

 stone in its neighborhood attendant upon its formation have given the metal- 

 bearing solution an opportunity of penetrating the rock, and although the 

 fissure itself may not have been the ore channel, the formation of the ore 

 bodies has been dependent upon it. 



Example of connections between ore bodies and fissures. NuUiei'OUS examples of an 



evident connection between ore bodies and fissures are to be found in this 

 district. Besides the east and west ore bodies of the Richmond mine, which 

 will be more fully desci'ibed hereafter, the Ruby-Dunderburg and Williams 

 mines, on Prospect Mountain, are among the best instances of this occur- 

 rence; but examples of fissures connected with ore bodies have been found 

 in almost all of the mines of the district. No doubt many of the deposits 

 in limestone which occur at numerous points in the Great Basin would 



