94 THE BINGEEA DIAMOND FIELD. 



The Newer Pleiocene di'ift afforded a few diamonds, and being 

 derived partly from the older drift, its materials are somewhat 

 similar ; but in addition to the gems as enumerated, a few grains 

 of osmiridium have been collected from it. 



Diamonds have also been found in Victoria, but in no large 

 quantities, and of but small size, but no report of their geological 

 position appears to have been published. 



AYe will now return to the more immediate subject of this note. 



The BiNaEEA Diamond Woekings. 



The diamond-bearing deposits at present undergoing develop- 

 ment are some seven or eight miles, more or less, to the south of 

 Bingera, and are situated in a kind of basin or closed valley 

 amidst the hills ; this basin is about four miles long by three 

 wide, and is open to the north. 



This, together with the surrounding district, is evidently of 

 Devonian or Carboniferous age, but all attempts to procure fossils 

 in order to vei'ify this have hitherto failed. As before mentioned, 

 the weather was too wet to allow me to make a proper search 

 myself; in fact, it was only with very great difficulty that one could 

 get about at all in the then state of the country. The weather 

 was so thiclc from the pouring rain and constant mists that but 

 meagre and unsatisfactory glimpses were obtained even of the 

 counti'y's general aspect. Nearly the whole of the basin seems 

 to have been originally more or less covered with drift, parts of 

 it having since been removed by denudation. 



Euuning into the valley are various spurs of basalt, which 

 apparently cover portions of the drift ; but at present this is only 

 a conjecture, since the workings have not yet been carried on 

 sufficiently far to show whether this be the case or not, neither by 

 tunnelling under it nor by sinking shafts, but I hope soon to 

 receive information upon this head, for when on the spot I sug- 

 gested that a shaft should be sunk which will decide the question. 

 Should the drift be proved to pass under the basalt, the known 

 diamond-bearing area will be greatly increased. The probabilities 

 are in favour that it does. 



Both the basalt and the drift have undergone much denudation. 



The drift is said to be ttaceable along the course of the river 

 for some (30) thii-ty miles. 



The drift is the forsaken bed of some river, and in all proba- 

 bility that of the Horton. 



The rock upon which the diamond drift rests, or the " bed rock" 

 of the minerals, is an argillaceous shale. Outcrops of this are 

 seen iu one or two places, but no good section is shown. 



