114 
The ore contains soluble sulphate and chloride—principally sodium. Some of the 
bismuth in the ore is in a form soluble in water. 
The experiments show that there should be no difficulty in direct treatment of this 
material by amalgamation and cyanide. 
The total extraction obtained was about 80 per cent, of total gold present. 
The consumption of cyanide was excessive (3 lb. per ton) : but this would be improved 
in practice, as an agitation test showed a much lower consumption. 
[12.5.14.1 
CUmA CLAY AT LIYTOYS. 
By W. Baragwanath, Senior Field Geologist. 
A deposit of china clay is situated in allotment 4, parish of Argyle, 
on the Lintons-Skipton-road, about 1 mile and a quarter south-east 
of the Junction Hotel. 
The formation consists of decomposed, highly felspathic, binary 
granite, an almost entire absence of mica being noticeable. Some of the 
material was taken from a shallow quarry, and placed as blinding on 
the adjacent roads. Where exposed to atmospheric agencies the kaolin 
has in places acquired a glaze with considerable hardness, but a shallow 
pit sunk by Mr. O’Meara, prior to my visit, shows the material to be 
much softer in the undried portion. 
A cursory examination shows the formation to be very extensive, 
probably underlying several square miles of country. In the quarry 
many veins of nearly pure kaolin intersect the decomposed ground mass 
of the rock. The colour of the material is snowy white, and very little 
iron staining is visible. Puddling will be necessary, and the quartz, 
which forms one quarter of the whole, will require washing off. The 
general appearance of the material suggests that the deposit may prove 
of value. 
A sample was tested at the Geological Survey laboratory by Mr. P. 
G. W. Bayly, who reports as follows;—“ The .sample (Yo. 65) is decom¬ 
posed granite with kaolinized felspar. It contained clean quartz grit, 
which was easily separated by washing from the fine white clay portion. 
The proportions were :— 
Percentaf^e. 
Quartz grit .. .. . • 56 
China clay . . .. .. 44 
The quartz is white to gray in colour. Test pieces were made up of the 
material after crushing fine, including the quartz (A) and also of the 
fine white washed clay free from grit (B). The pieces were dried and 
treated at various temperatures with the following results— 
(A) (B) 
Test 0, air-dried — 
Colour .. . . White . . 
Shrinkage .. . . 4 per cent. 
Test A, muffle heat, 1,100° Cent .— 
Colour . . . . White .. 
Shrinkage .. . . 4 per cent. 
Soft biscuit 
Test B, wind furnace, 1,340° Cent, {after muffle, twice 
Colour .. .. Dull white 
Shrinkage .. .. 11 per cent. 
Moderately hard 
Test C, wind furnace, 1,340° Cent, {once burned )— 
Colour .. .. Dull white 
Shrinkage .. .. 11 per cent. 
Moderately hard 
White 
6 per cent 
White 
11 per cent. 
.. /Harder biscuit 
burned )— 
. . WHte, shght iron 
(superficial) 
25 per cent. 
Dense, hard 
.. White, slight iron 
(superficial) 
., 25 per cent. 
.. Dense, hard 
stain 
stain 
