The Sunny Corner Project is 100% owned by GCR and is located midway between Bathurst and Lithgow, just north of the Great Western Highway. A joint venture agreement has been negotiated with Argent Minerals Limited (AM) whereby they can earn 70% interest by spending $686,000 by 2013. AM are focusing on silver and base metals and are planning to list on the ASX in early 2008.
Drilling by AM in 2007 failed to intersect any significant mineralisation however a more extensive exploration program is planned for 2008. This includes a VTEM survey designed to look for deep conductors associated with base metals and a 1,000 metre drilling program designed to look for downthrown extensions to known mineralisation in the project area. The geological model will be reviewed and revised with the aim to produce a JORC complaint resource estimate in the second half.
Modern mineral exploration has focused on the very high grade massive sulphides historically mined at Sunny Corner, where initially gold (12,000 ounces), then silver were extracted, with copper, lead and zinc largely going to waste at grades of up to 30% combined metal.
A total of 250,000 tonnes of sulphide ore was originally mined to produce approximately 3.5 million ounces of silver. Gold grades in the massive sulphide were reported to be in the order of 4.5 g/t.
In terms of gold-equivalent at today’s gold and silver prices this amounts to about 10 g/t gold-equivalent.
Most previous explorers have considered the old Sunny Corner Mine mineralisation represents ancient volcanic-hosted massive sulphide (VHMS) deposited on the seafloor some 420 million years ago. Mineralisation was thought to be deposited at the interface between volcanic and sedimentary rocks. GCR does not discount this theory, however geological evidence suggests that the old mine is hosted in a very large zone of crustal deformation and that faults within this zone exert considerable control on the distribution of ore minerals. GCR’s focus on structural controls on mineralisation opens up many more opportunities for discovery of new mineralised zones compared to the stratigraphic (VHMS) model previously considered.
GCR first became involved in Sunny Corner when it acquired the Licence from Michelago Resources in 2000. Some considerable time was spent consolidating tenure (which included old mining leases) into a new Exploration Licence (EL 5964) which was granted in August 2002. The drought and high fire risk in the area prevented all but reconnaissance work until about April 2003. Since that time GCR has conducted intensive geochemical sampling and geological mapping culminating in drilling in September 2003.
Geology
Sunny Corner lies within the Sunny Corner Synclinorium which occurs in the northern part of the Captains Flat – Goulburn Synclinorial zone in the eastern Lachlan Fold Belt. The area comprises a sequence of deformed and metamorphosed Silurian to Middle Devonian sedimentary and volcanic rocks that were intruded by Middle to Late Devonian granites.
The mineral deposits at Sunny Corner are hosted in a sequence of Siluro-Devonian rocks and later felsic porphyries, probably of Permo-Carboniferous age. The Siluro-Devonian comprises a basal conglomerate, overlain by felsic volcanic and volcaniclastic rock and siltstones. Sunny Corner is located on a parasitic anticline on the southwestern margin of a broad dome-like structure. Strong NW-SE structural trends are evident and appear to control emplacement of intrusive rocks. Whilst original interpretations indicate a volcanic-hosted massive sulphide setting for the historic Sunny Corner Mine, there is also geological evidence to suggest that mineralisation may be associated strong deformation and the emplacement of the younger intrusive rocks.
Gold Prospects
In August 2004, RC drilling was carried out at the Bobs Creek, Little Hill and Big Hill areas 1-2 km southwest of the main Sunny Corner village. Historically, a combined production of 15,000 ounces of gold was recorded from gold bearing quartz veins. GCR geologists have noted the presence of finely stockworked quartz veining within hydrothermally altered sedimentary rocks (Big Hill, Little Hill) and porphyritic intrusive rocks (Bobs Creek). At all three prospects, the mineralisation occurs either at the surface or close to surface.
Results of the drilling at Big Hill and Little Hill returned narrow, low grade intercepts, while broad low grade intersections were encountered at Bobs Creek. Follow-up drilling at Bob’s Creek in July 2005 encountered broad intersections (30 to 50 m) of anomalous gold (0.1 to 0.5g/t)
Base Metal Prospects
Geology
Geological work completed this year indicates that the old Sunny Corner Mine is hosted in a broad (600m wide) corridor of intense faulting and alteration which extends in a north-south orientation for in excess of 3.5km. This faulting occurs coincidentally with the north trending contact between fine sedimentary rocks and felsic volcanic rock and dip westward. Sulphide minerals rich in copper, lead, zinc (base-metals) arsenic, gold and silver occur in both types of rock in fault zones and in bedding parallel structures.
Geochemistry
GCR has undertaken extensive rock chip and soil sampling to determine the distribution of both base-metals and precious metals (gold and silver). Soil samples delineated a strong gold-silver-lead anomaly 1500m long and 100m to 200m wide. Within that zone, numerous anomalous rock chip samples have been collected. In places, continuous rock chip samples were collected from outcrops over intervals of between 1m – 4m. Weighted average composites were calculated up to sample widths of 14m. Significant results are tabulated below.
* Re-assay
Best results were returned from breccias that outcrop beneath exposed ore zones in the old open cut mine, and from silicified shear zones that crosscut ore horizons. The latter were previously identified by GCR as potential hosts to gold and silver mineralisation. Broad widths of lower grade mineralisation were also encountered surrounding high grade zones.
Drilling
Four drilling programmes totalling 49 RC drill holes have been completed since September 2003. Results include 10m at 1.7% copper, 10.8% lead, 18.6% zinc, 1 g/t gold and 177 g/t silver in hole GSC-36 and 5m at 245 g/t silver, 1.85 g/t gold, 0.8% copper, 6.0% lead and 6.6% zinc in Hole 42, which was drilled to intersect the same mineralised body 30m down dip. This result shows that the high grade massive sulphide mineralisation continues to extend down dip. This body is open down dip and to the north.
Results from the remainder of the holes confirm the presence of a specific mineralised horizon to the east of hole 42 and enhance the geological understanding of the area.
|
Hole No. |
AMG East (m) |
AMG North (m) |
From (m) |
Interval (m) |
Copper (%) |
Lead (%) |
Zinc (%) |
Gold (g/t) |
Silver (g/t) |
|
GSC-01
|
769150
|
6302930
|
22
|
16
|
0.2
|
0.4
|
1.9
|
0.03
|
5
|
|
GSC-03
|
769127
|
6302864
|
22
|
50
|
0.4
|
1.8
|
3.8
|
1.00
|
45
|
|
Incl
|
22
|
14
|
0.7
|
6.0
|
10.4
|
3.50
|
144
|
||
|
Incl
|
22
|
6
|
0.3
|
3.5
|
5.9
|
7.85
|
254
|
||
|
Incl
|
22
|
2
|
0.3
|
3.2
|
5.3
|
20.30
|
395
|
||
|
Incl
|
28
|
8
|
1.1
|
7.9
|
13.7
|
0.20
|
61
|
||
|
GSC-04
|
769137
|
6302864
|
50
|
10
|
0.2
|
0.8
|
1.6
|
0.02
|
4
|
|
Incl
|
54
|
2
|
0.4
|
2.1
|
3.7
|
0.02
|
7
|
||
|
GSC-05
|
769193
|
6302866
|
28
|
14
|
0.7
|
2.9
|
6.2
|
0.07
|
23
|
|
Incl
|
30
|
6
|
1.4
|
5.3
|
11.8
|
0.13
|
47
|
||
|
GSC-06
|
769235
|
6302866
|
10
|
36
|
0.7
|
1.8
|
4.7
|
0.13
|
37
|
|
Incl
|
12
|
6
|
2.5
|
0.3
|
2.0
|
0.18
|
87
|
||
|
Incl
|
18
|
8
|
0.7
|
5.2
|
13.6
|
0.11
|
55
|
||
|
Incl
|
18
|
4
|
1.0
|
7.3
|
21.4
|
0.17
|
83
|
||
|
GSC-08
|
769147
|
6302760
|
44
|
30
|
0.1
|
0.9
|
1.4
|
0.03
|
4
|
|
Incl
|
44
|
20
|
0.1
|
1.3
|
1.7
|
0.03
|
6
|
||
|
Incl
|
44
|
12
|
0.2
|
1.9
|
2.1
|
0.03
|
7
|
||
|
GSC-09
|
769037
|
6302760
|
54
|
6
|
-
|
-
|
-
|
0.14
|
6
|
|
GSC-10
|
769218
|
6302600
|
2
|
10
|
0.1
|
0.3
|
0.1
|
0.25
|
6
|
|
and
|
22
|
98
|
0.1
|
0.4
|
0.9
|
0.02
|
2
|
||
|
Incl
|
22
|
20
|
0.2
|
0.9
|
2.2
|
0.03
|
6
|
||
|
and
|
116
|
4
|
0.4
|
1.2
|
2.3
|
0.03
|
9
|
||
|
GSC-14
|
769062
|
6302863
|
36
|
50
|
0.4
|
0.6
|
2.4
|
0.07
|
16
|
|
incl
|
36
|
18
|
0.6
|
1.6
|
5.4
|
0.14
|
34
|
||
|
incl
|
38
|
4
|
0.8
|
3.3
|
8.8
|
0.27
|
47
|
||
|
GSC-19
|
769147
|
6302858
|
20
|
2
|
0.2
|
1.9
|
0.2
|
0.35
|
121
|
|
and
|
36
|
6
|
0.6
|
4.1
|
9.3
|
0.12
|
45
|
||
|
and
|
70
|
2
|
0.5
|
0.2
|
3.4
|
0.05
|
16
|
||
|
GSC-21
|
769224
|
6302846
|
16
|
2
|
0.1
|
1.5
|
1.6
|
1.37
|
109
|
|
and
|
48
|
6
|
1.6
|
0.5
|
5.8
|
0.06
|
29
|
||
|
GSC-23
|
769138
|
6302824
|
25
|
37
|
0.4
|
1.3
|
2.8
|
0.02
|
13
|
|
incl
|
25
|
13
|
0.7
|
3.4
|
6.5
|
0.14
|
30
|
||
|
incl
|
25
|
6
|
0.6
|
5.6
|
8.5
|
0.19
|
34
|
||
|
and
|
36
|
2
|
2.7
|
3.7
|
11.0
|
0.23
|
73
|
||
|
GSC-25
|
769151
|
6302801
|
19
|
9
|
0.9
|
6.2
|
7.6
|
0.07
|
38
|
|
incl
|
20
|
4
|
1.2
|
7.7
|
12.2
|
0.06
|
47
|
||
|
GSC-26
|
769142
|
6302800
|
22
|
10
|
0.8
|
4.3
|
10.8
|
0.11
|
36
|
|
incl
|
22
|
3
|
1.6
|
8.8
|
18.9
|
0.14
|
63
|
||
|
incl
|
22
|
2
|
1.1
|
11.8
|
19.1
|
0.14
|
18
|
||
|
GSC-31
|
769148
|
6302827
|
16
|
4
|
0.4
|
2.6
|
0.8
|
1.02
|
196
|
|
incl
|
16
|
1
|
1.3
|
8.0
|
0.9
|
3.00
|
628
|
||
|
GSC-32
|
769047
|
6302782
|
34
|
14
|
0.2
|
1.3
|
2.1
|
0.09
|
22
|
|
incl
|
36
|
2
|
0.6
|
2.9
|
5.4
|
0.12
|
62
|
||
|
and
|
52
|
4
|
0.2
|
1.0
|
2.3
|
0.18
|
33
|
||
|
GSC-36
|
769058
|
6302867
|
46
|
26
|
1.2
|
5.9
|
12.0
|
0.42
|
93
|
|
incl
|
46
|
10
|
1.7
|
10.8
|
18.6
|
1.00
|
177
|
||
|
GSC-37
|
769131
|
6302907
|
16
|
22
|
0.7
|
4.6
|
6.1
|
0.51
|
44
|
|
GSC-38
|
769065
|
6302897
|
38
|
18
|
0.1
|
0.7
|
1.2
|
0.31
|
3
|
|
GSC-39
|
769221
|
6302866
|
36
|
12
|
0.1
|
1.0
|
1.2
|
0.05
|
3
|
|
and
|
52
|
3
|
0.4
|
0.1
|
2.5
|
0.04
|
6
|
||
|
GSC-42
|
768992
|
6302882
|
87
|
5
|
0.8
|
6.0
|
6.6
|
1.85
|
245
|
|
GSC-44
|
769229
|
6302798
|
36
|
4
|
0.2
|
1.6
|
4.0
|
0.39
|
12
|
|
GSC-46
|
769229
|
6302603
|
18
|
4
|
0.1
|
0.6
|
1.9
|
0.02
|
6
|
This drilling is the first RC drilling to be undertaken on the prospect since the 1980′s and is of a reconnaissance nature, with the view to assessing geological controls on the distribution of mineralisation. It is clear that this programme has not tested all of the mineralised structures in the mine area and that systematic drill testing of all north-trending fault structures is required.
January, 2008