The Burra property is located 40 km east of Cobar in the highly prospective Canbelego-Mineral Hill volcanic belt of the Lachlan Fold Belt in central New South Wales. The Burra prospect was part of the much larger Canbelego tenement which was sold to Polymetals at the end of 2008. The Burra prospect has good potential for Cobar style copper-gold mineralisation with some history of exciting drill hole intersections. Drilling of 1,000 m of RC and diamond core commenced has commenced and results have been received and summarised below.
The prospect is located at the historic Burra Copper Mine that recorded minor production in the late 1880’s. A three hole RC and core drilling was carried out at the Burra Copper prospect during May and June, 2008 and a further 3 RC/core holes were drilled in early 2009. The presence of high grade copper intervals of up to 6.45% within broader intervals in the sulphide zone is particularly encouraging (see table below).
This drilling followed up on results from GCR’s 2004 program which returned:
- 11m at 3.1% copper from 140m
- including 2m at 13.7% copper
The drilling program intersected a north-south striking copper-rich zone. Minor lead-zinc mineralisation was also intersected and may form part of a zone related to the copper mineralisation or controlled by the northwest-trending contact zone between Ordovician Girilambone Beds and Devonian sediments and volcanics.
The new intersections confirm the continuity of mineralisation at Burra over an open 150m strike length and indicate down dip potential, beyond the existing 100m, with the mineralisation showing typical Cobar-style characteristics. Future drilling will be directed to test the zone at depth, as Cobar-style lenses generally have short strike lengths but deep extensions.
If the Burra Copper prospect can be advanced and resources subsequently defined, it will be well placed in terms of potential development options, with a number of operating mines and mills at Cobar and Tritton, within a 75 km radius.
Best results from the recent drilling program are set out below:
These and other intersections are shown in plan and sections in the following diagrams.
A 3D spin-through of the historical underground workings with drill hole intersections can be viewed below. In the spin-through the grey sheets are faults, the green sheet is a wireframe of the unconformity believed to be associated with the mineralisation and the underground workings are in orange. The drill traces have been coloured with copper grade with the following colour scheme -
blue > 0.1% Cu.
green > 0.2% Cu
orange > 0.4% Cu
red > 0.6% Cu
pink > 1% Cu