BY LEO A. COTTON. 505 



prospected for over 6000 feet along the line of outcrop. The 

 latest figures show that the mine has been worked continuously 

 for more than 4000 feet along the lode. North of its junction 

 with the King Conrad Lode the outcrop is not so well marked, 

 but two prospecting shafts sunk along the line of lode have both 

 shown ore-values. The lode has been mainly worked between 

 the King Conrad and the Conrad Shafts. These shafts have 

 been connected, at the 400-feet level, by a long drive along the 

 ore-body, and much of the ore has been stoped from this level, 

 practically, and in some cases actually, to the surface. From 

 the ground-level, at the Conrad Shaft, an adit has been driven 

 into the "Big Hill" for about 2000 feet; this is connected 

 with the surface by Moore's Shaft. The mouth of this latter 

 shaft is some 300 feet above tliat of the Conrad Shaft. The 

 accompanying section (text fig. 2) illustrates the positions of the 

 shafts referred to. 



The Conrad Lode, like the King Conrad, has a well defined 

 ore-shoot, pitching to the south-east at a steep angle. This is 

 represented by the shaded area in the figure. A very prominent 

 feature of this lode, in which it differs from the King Conrad, 

 is the presence of a conspicuous soft casing or " dig," as it is 

 termed. This occurs sometimes on one, and sometimes on the 

 other side of the fissure. It is always intermediate in position 

 to the lode and the country-rock. It varies from 2 to 9 inches 

 in width, and is of a clayey nature, with abundant quartz-grains 

 similar to those in the granite. The junction of this clay-selvage 

 with the granite-wall is frequently marked by slickensides; and 

 the strise are vertical in some cases, and horizontal in others. 

 The presence of this soft band is of great economic importance, 

 as it enables mining to be carried on at a minimum cost. 



As far as the mineralogical structure of the lode is concerned, 

 it resembles that of the King Conrad. The constituent minerals 

 are the same, consisting of arsenopyrite, pyrite, galena, sphalerite, 

 chalcopyrite, stannite, and quartz. In this lode the stannite, 

 though more abundant than in the King Conrad Lode, is yet only 

 .present in small quantity — the tin-content averaging about 0'5 % 



