143 
These rocks are near the limit of the area of metamorphism caused by the 
intrusive mass of granitic rocks to the north-west. Some of the slate 
beds (locally called lt vughy ”) are distinguished by rectangular cavities, 
once no doubt occupied by crystals of iron pyrites which have since dis¬ 
solved away. This rock closely resembles slates noted at Inkerman, 
Queen’s Birthday, and Windmill Hill reefs. The miners and prospectors 
consider it a good sign if the dark-blue slates have" a greasy feel and an 
irregular, glossy appearance. Both these features are evidently caused 
by movement in the rock. 
The indicator is parallel to the country rock in dip and strike. It 
consists of a thin quartz vein occurring along a plane of movement in a 
stratum of dark-blue slate, and has a well-polished and striated foot- 
wall. One series of striations is almost in the direction of the dip of the 
rocks, but has a tendency to dip northwards, and the dip of the 
other series is more decidedly to the north. The indicator is from i to 3 
inches thick, and finely laminated; in some parts consisting of as many 
as 50 layers of quartz to the inch. The thicker layers are white, and 
rather vitreous, with some blue mottlings, and the thinner layers are dark 
coloured, blue in places, and sugary in texture. The dark colour appears 
to be due to the inclusion of comminuted slate. It may be mentioned 
that during the progress of the survey of the Dunolly district thin 
layers of quartz were generally found to vary in colour with the con¬ 
taining rock, being, as a rule, white in light-coloured sandstones, &c., and 
dark-blue or blue and white in the dark-blue slates. It appears that the 
indicator has been formed by solutions flowing along the fissure and per¬ 
meating the slate walls and there depositing quartz. There is no gold 
in the indicator. 
A small quartz vein a few inches thick has been faulted by the in¬ 
dicator as shown in the diagram. Where it can be seen in a very small 
cross-cut it dips N. 10 deg. W. at 70 deg. The two- dissevered ends of 
this quartz vein were richly auriferous where they adjoined the indicator. 
The contact of the vein and the indicator pitches N. at 30 deg. in one 
place, and at others probably at a smaller angle. The gold is very 
limited in its occurrence, and quartz only a few inches away from the 
indicator is left untouched. It has been worked along the pitch of the 
intersection for about 300 feet to a depth of 80 feet from the surface, 
where water level was reached. Pumping machinery was then erected, 
but was not powerful enough to cope with the water, and the mine is now 
idle. ' The stone was payable along the whole distance worked; 10 oz. 
per ton was obtained, and in one instance 60 oz. of gold was yielded 
by one bucketful of ore. Afterwards quartz taken at some distance from 
the indicator gave 4 dwt. and 18 dwt. per ton. 
It appears that the slate bed containing the indicator offered less 
resistance than the surrounding rocks to pressure acting on them, and that 
in consequence it was fractured parallel to the bedding. The fracture 
became the channel through which a solution percolated, and this, where 
it came in contact with the solution which deposited the quartz vein in 
which the gold was found, led to chemical reaction which caused the 
deposition of gold. 
[Report sent in 16.12.07.'] 
B 2 
