174 
induced an alteration of the slate and its constituents. Not much below r 
because some examples show black slate studded with unaltered pyrites 
and traversed by turquoise veins, but such a case may be the extreme 
downward extension of a fissure in which the turquoise has formed from 
solutions filtering through the altering portions of the slate. 
The veins appear to have formed in precisely the same way as quartz 
veins. The fluid found, perhaps, a minute fissure, and deposited a thin 
film therein; to this film the segregation of other similar matter would 
follow, and gradually the fissure would widen and extend in all directions, 
being followed up and wedged open by still further accumulations. The 
incrustations on the sides of the tunnels plainly indicate that the process 
may still be in progress, and that turquoise may form even in artificial 
cavities. 
At the several localities, examples occur where the country rock is 
broken and the spaces are filled in with turquoise, forming a breccia. The 
veins range from mere films up to more than an inch wide, but the larger 
pieces are generally coarse, and of poor colour (pale green, &c.). Every 
stage of me growth of the mineral is to be seen in the various localities. 
In some cases, narrow joints have their sides thinly coated with mammil- 
lated turquoise, in others, the crack is nearly filled, or again, it is occupied 
by dense beautifully coloured mineral. After it has been formed, exposure 
to the atmosphere seems to cause it also to decay, for near the surface 
some very soft pieces and veins are met with. 
So far as mining for this gem stone is concerned, it seems, from present 
experiences, that such operations will be confined to the surface, and to 
moderate depths—30 to 40 feet—and, therefore, open workings will best 
answer the purpose. 
Some of the seams of turquoise are of a beautiful colour, and specimens 
kept for three years have not perceptibly faded or changed colour. No 
data was obtained on which an opinion could be based as to whether the 
turquoise can be profitably mined. Sufficient work has been done for this 
purpose, but no particulars as to the quantity and value of the turquoise 
are ascertainable. 
Quite lately, fissures in slate filled with turquoise similar in character 
to the above-described occurrences have been found a few miles from 
Benalla. 
[Report sent in 28.12.93.'] 
SOME MINES AT CHILTERN. 
By W. Baragwanath. 
The Golden Bar Mine. 
The Golden Bar Company have a main shaft sunk to a depth of 
350 feet, with two levels opened out east and west at 235 feet and 342 
feet respectively. At the No 1 level the Golden Bar reef was found 
26 feet to the east of the shaft. The general dip of the reef is to the east 
at 73 deg., and the general strike is N. 27 deg. W. The width of the 
reef varies from a few inches to 3 or 4 feet. 
