BY L. A. COTTON. 819 



The Star of the South has been more productive than any other 

 mine on this field. The bulk of the material mined was hauled 

 from Skippen's shaft, which is 90 feet in depth. The shaft was 

 sunk through basalt until the underlying granite was encountered- 

 The sinking was then continued into the granite, and two drives 

 put in to intersect the wash, and so drain the lead. Both drives 

 intersected a dyke nearly at right angles. In one drive, the dyke 

 attained a thickness of one foot, and in the other it was six inches. 

 The dyke-material was decomposed to a yellow clay. Boulders of 

 this clay were found in the diamond-bearing wash in association 

 with the gemstones. 



Adjoining the Star of the South Mine, is Benson's block, better 

 known as the Old Farm. The lead is here covered by 60 feet of 

 basalt, and a considerable amount of water was present in the 

 drift and gravels. The wash was of a very coarse nature, and 

 contained a great number of quartz-boulders up to six inches in 

 diameter. Boulders of granite were also abundant. The diamonds 

 recovered from this mine were similar to those found in the Star 

 of the South, and averaged from three to four to the carat. This 

 mine is of special interest, as here the lead terminates abruptly 

 at the northern end. This disappearance of the lead is explained 

 by the fact that, at this point, the Tertiary stream-channel has 

 been reopened by a recent watercourse, which has removed all 

 traces of the diamond-bearing gravels. The recent stream has 

 its channel on the floor of a steeply sloping gully, less than one 

 quarter of a mile in length, and joins Cope's Creek at a very 

 rugged spot. Beyond this, the lead must have crossed the 

 present position of Cope's Creek. About half a mile to the north- 

 west of this point, there is a large body of gravel and wash at an 

 elevation some 20 feet lower than the gravels at the Old Farm. 

 There can be no doubt that this was part of the main Tertiary 

 stream-channel. The gravels have been prospected by means of 

 tunnels, but no diamonds were found. A tributary flowed in at 

 this spot from the south-west, and recent denudation has exposed, 

 in several places, the gravels deposited along its course. These 

 deposits have been exploited, but without success. The course 

 of the main Tertiary stream has now been traced from Rider's 



