TIDMMML
RNS Number : 2765E
Medusa Mining Limited
05 April 2011
MEDUSA MINING LIMITED
ABN: 60 099 377 849
Unit 7, 11 Preston Street
Como WA 6152
PO Box 860
Canning Bridge WA 6153
Telephone: 618-9367 0601
Facsimile: 618-9367 0602
Email: admin@medusamining.com.au
Internet: www.medusamining.com.au
ANNOUNCEMENT
5 April 2011
Co-O DRILLING CONTINUES HIGH GRADE RESULTS
Medusa Mining Limited (ASX and AIM - MML; TSX - MLL) ("Medusa"
or the "Company"), through its Philippines operating company
Philsaga Mining Corporation ("Philsaga"), announces an update of
the Co-O Mine surface drilling results for previous holes MD290,
MD291, MD295, MD297 and MD298, and new holes MD300 to MD305, and
results from underground drilling and regional drilling around the
Co-O Mine up to 25 March 2011.
Highlights include:
Width Grade (uncut)
Hole Number (metres) (g/t gold)
-------------- ---------- --------------
MD298 2.00 219.17
-------------- ---------- --------------
MD302 0.80 42.33
-------------- ---------- --------------
MD303 1.00 31.45
-------------- ---------- --------------
EXP054 1.15 12.49
-------------- ---------- --------------
L5-028 4.80 13.84
-------------- ---------- --------------
L5-039 9.65 12.58
---------- --------------
L5-041 13.10 47.81
-------------- ---------- --------------
Exceptional results are being obtained from a new wide,
sub-vertical, high grade zone within the mine as shown by the
results in holes L5-039 and L5-041.
A recent assessment of the Co-O Mine vein architecture by
independent structural geology consultants described strong
similarities of the Co-O Vein system structure and aerial extent to
the Martha Mine epithermal vein system in New Zealand which
produced approximately 5.6 million ounces of gold from the 1870's
to 1952 and was mined to around 600 metres in depth.
Geoff Davis, Managing Director of Medusa, commented:
"The continuing good results from the Co-O Vein system and
surrounds are extremely pleasing, including the discovery of a new
exceptionally wide and high grade zone within the mine by
underground drilling.
I also wish to emphasise that, as we drill new vein systems,
drill intersections in veins rarely provide ore-grade intersections
in every hole. As our data base grows, and the characteristics of
each vein become clearer, statistical assessment of the percentage
of oregrade drill hole intersections required, maybe as low as 40%
of holes with ore grade intersections, will increasingly provide
the levels of certainty for turning exploration drill results into
ore that can be developed with confidence."
Co-O MINE DRILLING
Discussion
Figure 1 (please see the link at the end of this announcement)
shows all the new Co-O Mine MD series diamond drill holes from
MD300 to MD305 totalling 4,167 metres completed in six holes since
the last announcement on 18 January 2011 up to 25 March 2011 and
also previous holes MD290, 291, 295 and MD297 to MD298. It also
shows the regional EXP drill hole locations.
It should be noted that the 4 metres of 5.89 g/t gold in the top
of MD300 reflects quartz fragments in soil indicating a high grade
vein near the collar of the drill hole.
Surface drilling with two rigs on the mine area has focussed to
the east of the Oriental Fault, and regional drilling has continued
with four rigs.
Table I lists the surface diamond drilling results greater than
3 g/t gold from the Co-O Mine for new drill holes MD300 to MD305 as
well as results not previously reported for some earlier holes.
Assays are awaited for MD304 and MD305 and additional assays are
awaited for MD302.
Previous reports were published for holes numbered MD290 to
MD299 on 18 January 2011, MD261 to MD289 on 29 October 2010, MD241
to MD260 on 30 June 2010, MD217 to MD240 on 29 March 2010, for
holes below MD217 on 18 January 2010, 10 December 2009, 1 July
2009, 22 January 2009, 1 December 2008 and 12 August 2008. In 2007
the announcements are dated 9 July, 15 May and 28 February.
Figure 2 (please see the link at the end of this announcement)
shows the recently completed underground drilling totalling
6,723.50 metres in 29 holes. Table II lists underground drill hole
results since 18 January 2011. Completed holes drilled include
L2-040 and L2-041, L3-013 to L3-019, L4-010 and L4-011, and L5-028
to L5-033, L5-035 to L5-039, and L5-040 to L5-047. Assays are
awaited for holes L5-029, L5-034, L5-036 to L5-038, L5-040, and
L5-042 to L5-047.
Results down to 0.2 metres wide are reported since underground
development shows that in many cases as the veins approach
cross-cutting faults, they narrow down on both sides of the fault
over 5 to 10 metres before widening out, and hence the narrower
intersections are important in defining vein continuity. There is
also some pinching and swelling of veins along strike. Most
drilling is sub-parallel to the fault direction and rarely
intersects the faults, which are subsequently identified by
underground on-vein development.
Drill hole collar positions are surveyed by a qualified surveyor
and surface drill holes are surveyed downhole at regular intervals
using a digital multi-shot downhole camera.
It is important to note that the drilling of narrow epithermal
veins generally provides an indication of the presence of the gold
mineralised vein but may not always provide good quantitative data
with respect to accurate grade and volume estimations for some or
all of the following reasons:
-- Veins commonly pinch and swell and may be brecciated or
displaced by faults;
-- Gold distribution may be erratic; and
-- Drill core recovery may be reduced because of the brecciation
and soft unconsolidated material and hence the recovered material
may not be representative of the material drilled.
Consequently, the Company regards the initial drilling as
indicative only and operates the policy of using drilling to locate
the position and extent of the mineralised veins. This is then
followed by on-vein development to support the drilling results,
and to provide a more accurate estimate of vein grades which
results in the upgrading of the resource category from Inferred to
Indicated. The development supports the estimation of resources and
facilitates the conversion of resources to reserves.
Further information on narrow veins and the Company's policies
regarding exploration, development and resources-reserves is
contained on the Company's website, medusamining.com.au
Table I. Surface drill hole results >=3 g/t gold and >=0.2
metres downhole for new holes MD 300 to MD 305 and complete assays
for a previously partly reported holes designated * *
Grade
(uncut)
Hole Dip Azimuth From Width (g/t
number East North ([deg]) ([deg]) (metres) (metres) gold)
-------- ------- ------- -------- -------- --------- --------- -----------
MD290 27.20
** 613470 913217 -45 137 362.90 0.25 (*)
--------- --------- -----------
MD291
** 614223 913120 -55 192 334.10 1.20 4.13
--------- --------- -----------
378.40 0.55 11.92
--------- --------- -----------
445.80 0.40 3.16
--------- --------- -----------
452.60 1.40 5.69
--------- --------- -----------
578.20 0.25 5.28
-------- ------- ------- -------- -------- --------- --------- -----------
MD295
** 614223 913120 -65 193 118.45 0.20 17.75
--------- --------- -----------
400.45 5.65 6.05
--------- --------- -----------
462.00 0.60 6.16 (*)
--------- --------- -----------
30.61
569.80 0.35 (*)
--------- --------- -----------
612.90 0.50 3.41 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
MD297
** 614018 913157 -64 205 97.40 1.00 3.17 (*)
--------- --------- -----------
179.50 2.45 3.39 (*)
--------- --------- -----------
296.65 1.00 3.03 (*)
--------- --------- -----------
642.40 0.20 4.37 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
MD298 12.87
** 614160 913111 -50 193 265.45 0.65 (*)
--------- --------- -----------
276.30 0.40 3.21 (*)
--------- --------- -----------
328.60 0.30 3.32 (*)
--------- --------- -----------
219.17
425.40 2.00 (*)
--------- --------- -----------
14.07
443.10 1.10 (*)
--------- --------- -----------
489.20 1.60 7.89 (*)
--------- --------- -----------
23.99
569.60 0.40 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
MD300 614160 913113 -60 196 0.00 4.00 5.89 (*)
--------- --------- -----------
342.50 0.60 5.07 (*)
--------- --------- -----------
354.00 0.40 3.74 (*)
--------- --------- -----------
387.75 0.25 6.20 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
15.13
MD301 614020 913156 -55 188 143.65 0.55 (*)
--------- --------- -----------
153.70 0.30 4.74 (*)
--------- --------- -----------
156.25 0.25 8.60 (*)
--------- --------- -----------
163.50 0.35 9.93 (*)
--------- --------- -----------
196.90 0.20 5.20 (*)
--------- --------- -----------
218.90 0.35 4.78 (*)
--------- --------- -----------
346.55 0.20 3.27 (*)
--------- --------- -----------
549.75 0.55 4.57 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
MD302 614021 913156 -52 174 143.10 2.70 6.24 (*)
--------- --------- -----------
16.93
170.10 0.25 (*)
--------- --------- -----------
14.33
176.15 2.15 (*)
--------- --------- -----------
216.90 1.80 5.56 (*)
--------- --------- -----------
42.33
295.70 0.80 (*)
--------- --------- -----------
334.25 0.25 3.87 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
MD303 614114 913101 -57 206 55.00 2.50 7.76 (*)
--------- --------- -----------
54.70
205.80 0.85 (*)
--------- --------- -----------
315.35 1.00 4.05 (*)
--------- --------- -----------
321.65 0.40 4.26 (*)
--------- --------- -----------
31.45
366.35 1.00 (*)
--------- --------- -----------
400.60 0.80 3.70 (*)
--------- --------- -----------
429.50 0.60 6.30 (*)
--------- --------- -----------
439.70 0.40 3.23 (*)
--------- --------- -----------
591.30 0.25 4.04 (*)
--------- --------- -----------
610.00 0.80 5.81 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
Notes:
(i) Intersection widths are downhole drill widths not true
widths;
(ii) Assays denoted by (*) are by Philsaga Mining Corporation's
laboratory, all other assays are by McPhar Geoservices Inc. in
Manila;
(iii) Grid co-ordinates based on the Philippine Reference System
92.
Table II.Underground drill hole results >=3 g/t gold and
>=0.2 metres downhole.
Grade
(uncut)
Hole Dip Azimuth From Width (g/t
number East North ([deg]) ([deg]) (metres) (metres) gold)
--------- ------- ------- -------- -------- --------- --------- -----------
LEVEL 2
40.63
L2-040 613311 912873 3 228 66.50 0.45 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
L2-041 613313 912873 3 193 60.80 0.55 5.63 (*)
--------- --------- -----------
19.07
76.95 0.45 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
LEVEL 3
24.47
L3-014 613965 913136 3 36 61.40 0.60 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
L3-016 613730 912861 3 225 69.60 3.30 5.06 (*)
--------- --------- -----------
75.60 0.80 4.67 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
22.67
L3-017 613728 912863 3 231 38.50 0.40 (*)
--------- --------- -----------
17.58
102.10 0.60 (*)
--------- --------- -----------
107.00 0.20 4.87 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
L3-018 613725 912749 3 72 69.90 0.30 4.20 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
124.03
L3-019 613723 912751 3 49 52.90 0.30 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
LEVEL 4
L4-010 613563 912804 3 359 43.05 3.05 5.32 (*)
--------- --------- -----------
73.40 0.30 6.37 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
L4-011 613561 912804 3 322 95.75 1.40 3.59 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
LEVEL 5
L5-027 613942 912887 -19 203 71.80 1.20 4.93 (*)
--------- --------- -----------
17.77
75.90 0.20 (*)
--------- --------- -----------
77.75 0.20 3.17 (*)
--------- --------- -----------
11.61
227.70 0.20 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
L5-028* 614136 912893 -19 190 25.30 0.50 3.63 (*)
--------- --------- -----------
10.41
69.70 0.60 (*)
--------- --------- -----------
13.84
162.40 4.80 (*)
--------- --------- -----------
49.93
208.20 0.80 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
56.03
L5-030 614137 912894 -19 174 206.80 0.45 (*)
--------- --------- -----------
12.23
251.50 0.25 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
21.00
L5-031 613945 912887 0 140 25.35 0.30 (*)
--------- --------- -----------
16.03
76.40 0.45 (*)
--------- --------- -----------
10.73
88.65 0.30 (*)
--------- --------- -----------
120.05 1.50 6.38 (*)
--------- --------- -----------
38.33
131.10 0.35 (*)
--------- --------- -----------
143.80 3.70 7.31 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
25.15
L5-032 614141 912898 -19 140 62.20 0.25 (*)
--------- --------- -----------
23.80
118.30 0.40 (*)
--------- --------- -----------
128.45 0.35 3.23 (*)
--------- --------- -----------
139.00 0.20 8.43 (*)
--------- --------- -----------
141.15 0.25 3.76 (*)
--------- --------- -----------
187.80 0.40 8.80 (*)
--------- --------- -----------
223.40 0.60 3.65 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
13.47
L5-033 613943 912887 0 162 55.10 0.60 (*)
--------- --------- -----------
23.98
106.10 0.25 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
27.96
L5-034 613942 912887 0 183 110.40 0.55 (*)
--------- --------- -----------
38.61
115.70 0.20 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
L5-035 613942 912887 0 200 47.90 0.40 4.96 (*)
--------- --------- -----------
44.20
114.35 0.40 (*)
--------- --------- -----------
116.05 0.25 6.60 (*)
--------- --------- -----------
117.10 0.80 7.93 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
12.58
L5-039 613943 912887 -53 187 180.95 9.65 (*)
--------- ------- ------- -------- -------- --------- --------- -----------
L5-041 613943 912887 -53 183 162.80 13.10 47.81(*)
--------- ------- ------- -------- -------- --------- --------- -----------
Notes:
(i) Intersection widths are downhole drill widths not true
widths;
(ii) Assays denoted by (*) are by Philsaga Mining Corporation's
laboratory, all other assays are by McPhar Geoservices Inc. in
Manila;
(iii) Grid co-ordinates based on the Philippine Reference System
92.
Structural assessment of the Co-O Mine vein architecture
A recent assessment of the Co-O Mine's vein architecture by
independent consultants advised that the vein architecture is very
similar to the Martha Mine in the Hauraki Goldfield of New Zealand.
This mine commenced operation in 1880 based on high grade
epithermal quartz veins and up until 1951 had produced 5 million
ounces of gold and 11 million ounces of silver. The mine re-opened
as an open pit in 1987 (Crown Minerals, 2004).
The Martha Mine consisted of an extensive (1600 metres long by
500 metres wide) braided system of four main sub-parallel veins,
the Martha, Welcome, Empire and Royal) which were mined to a depth
of over 600 metres (Brathwaite and McKay, 1989). Similarly, the
areal extent of the current resources at Co-O is approximately
1,500 metres long by 500 metres wide, and level development is just
starting at 250 metres below surface on the eastern side of the
Oriental Fault just below the tops of some of the veins which top
out at between 150-200 metres below surface, indicating extensive
depth extensions likely remain to be explored and developed.
Co-O REGIONAL DRILLING
Using the Co-O Mine as a model, drill testing commenced in the
September quarter of 2009 on veins in the region of the Co-O
Mine.
The Co-O vein system Central Vein outcrops at surface on the
western side of the Oriental Fault, where it was first discovered.
The veins at surface rarely exceed 0.5 metres width and generally
assay around 1 to 5 g/t gold (with possibly some supergene
enrichment which is an increased concentration of minerals due to
weathering of the near surface mineralisation). Gold values on the
Central Vein start to increase significantly approximately 80
metres below surface.
It should also be noted that the drilling in the late 1980s and
early 1990s to locate the veins east of the Oriental Fault
intersected clay - minor silica alteration zones up dip from the
high grade veins, and returned assays up to 1 g/t gold which were
considered inconsequential at the time. Hence the Company carefully
evaluates the importance of low assays in geologically favourable
settings.
Figure 1 (please see the link at the end of this announcement)
shows the positions of the 11 holes EXP054 to EXP065 for a total of
8,246 metres. Table III shows the results >3 g/t gold over
>0.2 metres. Results for EXP001 to EXP012 were announced on 17
December 2009, an update up to EXP022 was provided on 19 March
2010, holes EXP022 to EXP028 were provided on 30 June 2010, for
holes EXP029 to EXP037 on 29 October 2010 and for holes EXP038 to
EXP053 on 18 January 2011.
Additional assay results are awaited for EXP063 and EXP064.
The grade trends, alteration types and vein mineralogies
emerging from some of the NT veins suggest that the drilling may
still be high up in the mineralisation system, in a similar manner
to the late 1980s drilling east of the Oriental Fault. This early
drilling intersected clay alteration zones with minor veining, but
the fully formed veins were not intersected until nearly 200 metres
below the present surface. If the vertical displacement component
of the Oriental Fault is added, and erosion, then the tops of the
well formed veins may have been well in excess of 200 metres below
surface.
Table III. Regional drill hole EXP 054-065 results >=3g/t
gold and >=0.2 metres downhole
Grade
(uncut)
Hole Dip Azimuth From Width (g/t
number East North ([deg]) ([deg]) (metres) (metres) gold)
-------- ------- ------- -------- -------- --------- --------- -----------
EXP054 614102 913410 -50 160 675.70 0.35 23.19 (*)
--------- --------- -----------
710.60 1.15 12.49 (*)
--------- --------- -----------
782.25 0.55 8.29 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
EXP055 613438 913741 -50 180 586.55 0.70 5.10 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
EXP056 613699 913646 -50 180 708.80 0.20 6.93 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
EXP061 613640 913452 -50 180 335.25 0.45 14.67 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
EXP062 614354 913289 -50 160 482.20 0.70 30.43 (*)
--------- --------- -----------
594.15 1.00 8.87 (*)
--------- --------- -----------
736.10 1.00 3.74 (*)
--------- --------- -----------
772.30 0.45 4.37 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
EXP064 613972 913316 -50 160 348.50 1.00 3.42 (*)
--------- --------- -----------
450.00 0.45 3.10 (*)
-------- ------- ------- -------- -------- --------- --------- -----------
Notes:
(i) Intersection widths are downhole drill widths not true
widths;
(ii) Assays denoted by (*) are by Philsaga Mining Corporation's
laboratory, all other assays are by McPhar Geoservices Inc. in
Manila;
(iii) Grid coordinates based on the Philippine Reference System
92.
ON-GOING DRILL PROGRAMME
It is intended that two surface rigs (which may be reduced to
one depending on progress) will continue drilling on the Co-O Mine
area and four rigs will continue regional drilling. Four drill rigs
will continue operating underground.
DRILL HOLE SAMPLING AND ASSAYING PROCEDURES
Samples are taken from mainly HQ sized (hole outside diameter 96
mm, hole inside diameter 63.5mm) and some NQ sized (hole outside
diameter 75.8 mm, hole inside diameter 47.6 mm) drill core. The
selected sample intervals are halved by diamond saw and half the
core was bagged, numbered and sent to the Company laboratory. In a
small number of cases to confirm the geological logging, the
selected interval was re-split and [1/4] core re-submitted for
assay.
Initial sample preparation and assaying is undertaken at the
Company's on-site laboratory. Samples are dried at 105 C for 6 to 8
hours, crushed to less than 1.25 cm by jaw crusher, re-crushed to
less than 3 mm using a secondary crusher followed by ring grinding
of 700 to 800 grams of sample to nominal particle size of less than
200 mesh. Barren rock wash is used between samples in the
preparation equipment. The samples are assayed by fire assay with
Atomic Absorption Spectrometer (AAS) finish on a 30 gram sample.
All assays over 5 g/t gold are re-assayed using gravimetric fire
assay techniques on a 30 gram sample.
Check assaying of the majority of samples used in the yearly
resource estimates is undertaken by McPhar Geoservices Phils Inc
("McPhar"), a NATA and ISO 9001/2000 accredited laboratory in
Manila. The pulps are airfreighted to McPhar who fire assay 30
grams of samples using AAS finish and a selected number of samples
are checked using gravimetric fire assay techniques. Duplicate
samples and standards are included in each batch of check
samples.
When reporting results, where available, the assays of McPhar as
an independent laboratory have been given priority over the Company
laboratory's results.
REFERENCES
Brathwaite, R.L. and Mckay, D.F., 1989: Geology and Exploration
of the Martha Hill gold-Silver Deposit, Waihi. In Mineral Deposits
of New Zealand, Monograph 13, Aust. IMM, Ed David Kear.
Crown Minerals, 2004: Ministry of Economic Development New
Zealand. Website: crownminerals.govt.nz
Click on, or paste the following link into your web browser, to
view the associated PDF document.
http://www.rns-pdf.londonstockexchange.com/rns/2765E_-2011-4-4.pdf
For further information please contact:
Australia
Medusa Mining Limited +61 8 9367 0601
Geoffrey Davis, Managing
Director
Roy Daniel, Finance Director
United Kingdom
Fairfax I.S. PLC +44 (0)20 7598 5368
Financial Adviser and Broker
Ewan Leggat/Laura Littley
Lothbury Financial Services
Limited +44 (0)20 7868 2010
Michael Padley
Canada
Nicholas Sayce, Investor
Relations +1 416 822 4404
Information in this report relating to Exploration Results has
been reviewed and is based on information compiled by Mr Geoff
Davis, who is a member of The Australian Institute of
Geoscientists. Mr Davis is the Managing Director of Medusa Mining
Limited and has sufficient experience which is relevant to the
style of mineralisation and type of deposits 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 Exploration Results, Mineral
Resources and Ore Reserves" and is a "Qualified Person" as defined
in "National Instrument 43-101" of the Canadian Securities
Administrators. Mr Davis consents to the inclusion in the report of
the matters based on his information in the form and context in
which it appears.
Refer to the Technical Report which was filed on Sedar in August
2010 for further discussion of the Co-O Deposit's geology,
structural controls, drilling, sampling and assaying information,
and any known material environmental, permitting, legal, title,
taxation, socio-political, marketing or other relevant issue.
DISCLAIMER
This announcement may contain certain forward-looking
statements. The words 'anticipate', 'believe', 'expect', 'project',
'forecast', 'estimate', 'likely', 'intend', 'should', 'could',
'may', 'target', 'plan' and other similar expressions are intended
to identify forward-looking statements. Indications of, and
guidance on, future earnings and financial position and performance
are also forward-looking statements.
Such forward-looking statements are not guarantees of future
performance and involve known and unknown risks, uncertainties and
other factors, many of which are beyond the control of Medusa, and
its officers, employees, agents and associates, that may cause
actual results to differ materially from those expressed or implied
in such statements.
Actual results, performance or outcomes may differ materially
from any projections and forward-looking statements and the
assumptions on which those assumptions are based.
You should not place undue reliance on forward-looking
statements and neither Medusa nor any of its directors, employees,
servants or agents assume any obligation to update such
information.
This information is provided by RNS
The company news service from the London Stock Exchange
END
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