spectacular near surface copper grades redbank

Redbank Mines Limited
Spectacular near surface copper grades at
Redbank
As part of the Redbank Oxide Copper Project
expansion definitive feasibility study (DFS) resource
infill and definition drilling is being carried out on the
Bluff, Azurite and Redbank deposits. This will enable
detailed pit planning and mine scheduling to be
completed. Interim results from this programme for
Azurite were announced on the 3rd of April.
Subsequently infill drilling has been completed at the
nearby Redbank Deposit. The drilling has
encountered a number of very high grade copper
intercepts in near surface oxide mineralisation,
including 29m at 7.7% copper and 24m at 4.54%
copper. The field programme has also located the
source breccia pipe for the Redbank mineralisation.
A total of 8 shallow drill holes were drilled for a total of
367m. As with the previously reported drilling at
Azurite, preliminary assaying of the holes has been
completed using field portable XRF (refer Table 1).
Quality assurance and quality control routines
demonstrate that these results are satisfactorily
consistent and reproducible and typically within 15%
of conventional laboratory assays. These results are
reported as interim results and should be regarded as
indicative pending reporting of final laboratory assays
expected in 4 to 6 weeks.
Highlights from the drilling to date at Redbank:
Hole No
length grade
Cu
from
RB08-10 23 m 2.95% from surface,
including 5 m @ 7.6%, 5 m @
4.15% and 4 m @ 0.83%
RB08-11 10 m 1.45% 1 m
RB08-12 10 m
5 m
1.05%
1.35%
25 m
38 m
RB08-13 24 m 4.54% from 15 m,
including 7 m @ 11.34%
RB08-14 29 m 7.70%* from 13 m,
including 9 m @ 13.18%*
RB08-16 5 m 1.10% 30 m
* RB08-14 terminated at 42m in mineralisation due to water
influx
Redbank Mines Limited
ASX Announcement – ASX Announcement 7 April 2008 2
RC Drilling at Redbank – March/April 2008
The drill holes were located around a shallow open pit (<4m deep) (Figure 1) from small
scale mining carried out between 1916 and about 1960s. Wet season rains have flooded the
pit to a depth of several metres preventing access to the pit floor. The drill holes were
oriented to test the perimeter and immediately below the pit. Previously drilling by Redbank
Mines Limited has identified a broad zone of oxide copper mineralisation extending from
surface to about 35m.
This programme has further tested the oxide mineralisation and found zones of very high
grade within the deposit corresponding to the source breccia pipe which was not located in
previous drilling. As with the other known breccia pipes in the area the Redbank pipe is a
discrete circular near vertical body. Supergene processes have enriched the breccia pipe as
well as dispersing the oxide copper mineralisation into the surrounding host rocks.
Previous inferred resource estimates for the Redbank Deposit indicate a grade of 1.51%
copper. This latest drilling could be expected to significantly enhance the average grade. The
breccia pipe remains open below the deepest intercepts at about 60 to 70m. Mineralised
breccia pipes at the Sandy Flat and Bluff deposits have been shown to extend through the
entire 250 to 300m thickness of the host Gold Creek Volcanics.
Yours faithfully,
Redbank Mines Limited
Jerome G Vitale
Managing Director
Competent Person:
The information contained in this announcement, insofar as it relates to the Company’s exploration results at
the Redbank Copper Project, is sourced from information compiled by Dr D James Searle, B.Sc, PhD,
MAusIMM,. Dr Searle is an Executive Director of Redbank Mines Limited and has sufficient expertise relevant
to the style of mineralisation and type of deposit under consideration and to the activity which he is undertaking
to qualify as a Competent Person as defined in the 2004 Edition of the ‘Australasian Code for Reporting of
Mineral Resources and Reserves’. Dr Searle has approved the inclusion of the statement in the form and
context which it appears.
Redbank Mines Limited
ASX Announcement – ASX Announcement 7 April 2008 3
Figure 1
Redbank Resource Definition RC Drilling
Redbank Mines Limited
ASX Announcement – ASX Announcement 7 April 2008 4
Table 1
Significant (>0.5% Cu) interim results from infill and resource definition drilling at the
Redbank Deposit. Final results will be reported when available in 4 to 6 weeks. Easting and
northing are in GDA94 format +/1m.
Hole No
Easting
m
Northing
m
Az/Dec
Deg. From m To m
Intercept
m Cu %
RB08-10 793140 8098810 000/60 0 23 23 2.95
inc 5 7.60
31 36 5 4.15
55 59 4 0.83
RB08-11 793140 8098790 000/60 1 11 10 1.45
14 16 2 0.90
24 31 7 0.80
RB08-12 793130 8098800 000/60 1 4 3 0.71
6 9 3 0.76
25 35 10 1.05
38 43 5 1.35
47 49 2 1.24
RB08-13 793110 8098320 090/60 15 39 24 4.54
inc 7 11.34
RB08-14 793110 8098310 090/60 13 42 29 7.70*
Inc 9 13.18
RB08-16 793146 8098841 238/60 13 15 2 0.76
30 35 5 1.10
* RB08-14 terminated at 42m in mineralisation due to water influx/