80 NOTES ON SOME MINERALS. 



planes of the mineral, are very handsome. Very beautiful 

 specimens are obtained by dissolving the calcite, as the gold is 

 then left in the most peculiar and fantastic forms. The auriferous 

 calcite is found, in veins traversing clay slates. 



At Bingera, two miles S.E. from the town, in serpentine. A 

 sample gave a return for gold at the rate of 9 dwts. per ton. 

 The calcite in this locality differs from the auriferous calcite of 

 Tea-tree Creek before mentioned, in being made up of thin plates, 

 which are contorted and interlocked. The laminse are, however, 

 easily separated, and the surfaces are seen to be dull. These 

 separated, thin plates are easily broken across in one direction, 

 exhibiting small bright cleavage planes. The contained gold 

 occurs in isolated particles, the largest of which would not be 

 more than - 2 - - grain in weight. Small crystals of pyrite are also 

 present in the calcite. 



Native Antimony. 



At Hillgrove Antimony Mines, fifteen miles easterly from 

 Armidale (N.E.), in small isolated deposits in the vicinity of veins 

 of stibnite. Amorphous, compact, colour and streak tin white. 

 Hardness between 3 and 4, scratches calcite, Sp. G. 6, 69. 

 Fracture irregular, rough ; cleavage on small faces, imperfect. 

 B.B. fuses easily, and becomes covered with prismatic crystals of 

 oxide of antimony. Not of common occurrence. The country is 

 principally of slate, more or less altered, and inclined from the 

 horizontal at a high angle. On the northern side of the mines 

 gneissic rocks are found outcropping. The principal mineral 

 veins of the locality are found in the slates, and are composed of 

 an amorphous quartz as the matrix. These quartz veins are in 

 places accompanied by casings of a tough greyish rock, composed 

 of whitish to colourless felspar, and dark green hornblende. At 

 low levels in the ravines on the southern side of the principal 

 mines this rock, which is probably a trachyte, is found as 

 intrusive sheets, which appear in some measure to follow the 

 bedding of the slates. 



Antimonite (Stibnite). 

 At the Hillgrove Mines before mentioned, associated with 

 arsenic and gold, in quartz veins traversing slates. The best 

 deposits of stibnite are generally found on the outer sides of the 

 veins, near either the ' hanging ' or ' foot ' walls, but more or less 

 of the ore is distributed through the quartz. Pyrite in small 

 quantities is found in the stone, but no mispickel nor arsenical 

 iron was observed, so that in what form the arsenic exists in the 

 ore has not yet been ascertained. The antimony mines of this 

 locality are now worked principally for the gold present in the 

 quartz, as the low price of antimonial ore, at the present time, 

 renders it of only secondary importance. 



