THE ORIENTAL REEF, WANDILIGONG. 
By E. J. Dunn, F.G.S., Director, Geological Survey. 
This reef is about i mile distant from Wandiligong in a north-easterly 
direction. Strike of reef N. 20 deg. W. ; dip slightly to the west but nearly 
vertical. At the west end of the outcrop the country rock dips E. 55 deg., 
so that the reef cuts right across the beds. The strike of the country rock 
was not clear. 
The outcrop was on the slope of the range and was of unusual thickness 
and length, in fact this was the most considerable as regards the bulk of 
quartz, and was one of the richest in gold in the district. In some parts 
the reef was from 40 to 50 feet wide, and it has been worked at the surface 
for a length of 2,000 feet. Landslips have occurred for hundreds of feet 
up the hillside above the workings. For years it was the mainstay of the 
gold-fields. 
Yellow, red, and grey sandstone and slate form the country rock which 
has more resemblance to Silurian than to Ordovician strata. The rocks are 
very much crushed. In depth the reef splits up, and at 400 feet from the 
surface, there are four reefs. At the north end also the reef splits up. 
The principal stoping was done from the surface to a depth of 250 feet. 
At the lower levels tunnels are 1 driven in, but although there are quartz 
reefs of fair thickness, the gold content is not payable, and so far the 
efforts made to discover richer quartz in the lower levels have not been 
successful. 
At the south end of the reef a large dioritic dyke occurs that Mr. Kennv 
pointed out to me. It is on the west side of the reef; whether this has had 
any influence on the occurrence of gold in this reef could scarcely be 
determined now unless the old workings show its relation to the reef at 
different points. 
From this reef an enormous quantity of quartz was crushed and a 
great deal of gold won, and for manv vears it afforded emplovment for a 
considerable number of miners and others, and when the yields fell off a 
local syndicate was formed to test the countrv at a much lower depth. The 
syndicate was called the Bright District Prospecting and Gold Mining Co., 
and for about 20 years this svndicate has been engaged in driving a tunnel 
which would cut the continuation of the reef at about 1.200 feet below the 
outcrop. The tunnel has been driven ^,8^0 feet and has reached the spot 
where the southern extension of the reef should be cut, but so far no reef 
of value has been disclosed. 
Unfortunately the cross-cut, driven for such a great length, has been 
through a barren zone of country, and therefore it has been of no value for 
prospecting purposes along its course. The area that should now be pro¬ 
spected by means of the tunnel lies below the old working, but this is held 
bv another company. Such long tunnels under circumstances of this kind 
are not the best or most economical means of testing reefs in depth and 
they are seldom of any value for prospecting purposes. 
Mr. Kenny will furnish plan and report on this reef. 
[Report sent in 20 .to.o 6 \ 
