Copper Hill

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The flagship 100%-owned Copper Hill project is near Molong in central New South Wales, about four hours drive from Sydney via Orange.

Copper Hill Resource Estimate
535,000 tonnes of copper and 1.47 million ounces of gold
contained within
173 million tonnes at 0.31 percent copper and 0.26 grams per tonne gold

The project is now well advanced into Feasibility Study Stage 2. A Project Manager has been appointed to lead an experienced and very capable team of mining engineers, geologists, metallurgists and environmental scientists who are proceeding to push the project forward.

Completion of a Definitive Feasibility Study is planned for the end of 2011 with a Bankable Feasibility Study, acceptable to Chinese or other financiers, now scheduled for mid-2012.

Exploration is on-going with two drilling rigs on site and definition of the first-pass oxide gold-copper resource is almost complete. Recent drill intersections have extended and improved the known resource.

Figure 1: Golden Cross Resources’
wholly owned Projects and Prospects

Copper-Gold (Golden Cross 100%)
Copper Hill is well located with respect to other copper-gold developments in the Ordovician Macquarie Arc of NSW (Figure 2). It is the Company's most advanced project, with currently defined resources containing 535,000 tonnes of copper and 1.47 million ounces of gold.

During the past year studies were aimed at reducing the estimated capital costs of the project and increasing the projected revenue by maximising the recoveries of all the economic elements (copper, gold and sulphur) from the deposit. Following economic analysis in Stage 1 of the Feasibility Study the roaster option has been put on hold and the current strategy is to produce a copper-gold sulphide concentrate for sale to smelters.

Figure 2: Copper Hill Project and Cargo Prospect –
Regional Location

 

Resource and Economics
The Copper Hill Resource, using a 0.2% copper cut-off grade, is summarised in the following table.

Table 1: Copper Hill JORC-Compliant Resources,
0.2% Cu cut-off, October 2010

Economically positive development attributes include improved copper and gold prices, a low waste to ore ratio, and ready access to excellent road, rail and power infrastructure. There is also a supportive local community.

Feasibility Study
Internationally renowned Nanchang-based Mine Design Group NERIN was retained to conduct Stage 1 of the Feasibility Study which was completed in January 2011. NERIN's engineers and technicians modelled mine outputs, mill throughputs, costs and recoveries based on the earlier 133 million tonne Resource. NERIN examined the supply, costs and quality of the capital equipment required for a fully integrated mill and processing plants for Copper Hill including the roaster-acid plant-SXEW-CIL complex proposed for Port Pirie. The capital costs (+$700 million) for this strategy, and the difficulties in producing a satisfactory sulphide concentrate to be railed from Copper Hill, rendered this approach uneconomic.

A more straight-forward and standard approach of producing a copper-gold concentrate for sale to smelters is now being studied. Much of the previous information and analysis of the project can be applied to Stage 2 of the Feasibility Study which has now commenced using an in-house team.

Mark Moddejongen, a senior mining engineering consultant has been appointed Project Manager for Copper Hill. Mark has over 30 years Australian and International experience in feasibility studies, mine planning and operational experience. Richard Lewis, a geologist who spent almost 20 years with Placer Pacific, was a senior member of the Placer teams which built mines like Kidston, Porgera, Misima, Granny Smith, La Coipa and Osborne. Lindsay Gilligan has also joined the leadership team from his previous job as Director of the NSW Geological Survey. Lindsay's experience and contacts with government will help guide the Copper Hill development through the regulatory and approvals process.

Mark, Richard and Lindsay will provide leadership and counsel to an already determined team of geologists, metallurgists and engineers focused on bringing Copper Hill to production within the next four years.

Capital Cost Reduction
Efforts are being made to reduce capital costs by identifying the best value processing equipment suppliers in China. This is being assisted by Golden Cross' major shareholder, China United Mining Investment Corporation, which continues to provide valuable commercial introductions to other Chinese organizations including China National Automation Control System Corporation (CACS). CACS may be party to a copper off-take agreement with GCR, subject to successful feasibility, financing and commissioning.

Metallurgy
Laboratory test work is continuing at Metcon to determine the flotation response of a composite sample representing typical Copper Hill mineralisation using a range of grind sizes, acidity levels (pH) and reagents. About 9 tonnes of PQ core was obtained from four holes in the metallurgical program completed in late 2010. This material is being crushed and assayed prior to sorting and compositing for testing at Metcon. A further 400 kg of composite will be sent to BGRIMM in Beijing for testing to satisfy potential Chinese financiers.

Recent drilling, core examination and consequent geological interpretations suggests clear potential for further improvement in metallurgical results by tailoring the flotation conditions and reagent suite to better match the mineralogy of the ore as it arises rather than masking this typical variation by compositing into one bulk sample. An increased 2-5% recovery for both metals at this stage in the flow-sheet would essentially report to the bottom line. Based on porphyry copper ores elsewhere, it is a realistic target for such optimisation studies.

A sulphide concentrate of 24-25% copper grade with 17 g/t gold (at 70% copper and 42% gold respective recoveries) was achieved from a few early exploratory tests. The low gold recovery suggested better returns from the bulk sulphide route. No leaching tests for gold recovery were run from the flotation tail as the gold price at the time was too low. The returns from such a tail leach today would be undoubtedly superior and this option is being carefully re-examined. Early tests to achieve a clean gold-bearing pyrite float from the tail are encouraging but much more work has to be done.

Desktop studies are continuing on the economics of marketable by-products although high capital costs have deterred, for the moment, further consideration to recover sulphur. Golden Cross has also conducted preliminary investigations into sharing the plant operating and capital costs with holders of similar sulphide deposits within the region or to ship gold-bearing pyritic tails to nearby operations with operating CIL plants.

Resource Development and Exploration
In 2010 a total of 3,902 metres of drilling was completed in 15 reverse circulation percussion and cored drill holes. The drill holes were designed to increase resources by testing strike and depth extensions of previously intersected mineralisation.
Significant results in terms of grade, length, and exploration potential have been returned from north and south ends of the Copper Hill Intrusion Complex.
Very good results were returned in GCHR298, drilled to test the 400RL- 300RL level beneath previously intersected near-surface mineralisation at Buckley's Hill (Figure 3). The intercept in GCHR298 generates down--dip, down-plunge and strike extension targets that will be followed up with further drilling.
Geological modelling of the Copper Hill Intrusion Complex and associated mineralisation was undertaken as a preliminary step to exploration target generation using porphyry copper models.
These included the wall-rock porphyry copper model exemplified by the Cadia East gold-copper deposits, located 55 kilometres south-east of Copper Hill.

Figure 3: GCHR265 and GCHR298 – Buckley’s Hill

This was supported by follow-up drilling in GCHR314 which returned wide intervals of higher grade.
Assay results from GCHR314 at a 0.2% copper cut-off the hole intersected 5 metres @ 0.47% Cu, 0.21 g/t Au from 77m metres, 63 metres @ 0.48% Cu, 0.23 g/t Au from 98 metres and 66 metres @ 0.61% Cu, 0.36 g/t Au from 186 metres.

Peak values for copper are 1.19%, 1.46% and 1.72% respectively. The two broad intercepts occur within a 154 metre long mineralised zone which is cut by a 24 metre-wide barren dyke. Metre intervals quoted are down-hole and approximate true thickness based on current geological interpretations. Gold assays correlate well with the copper zones. (Figure 4)

Fig 4: Follow-up drilling in hole GCHR314. Assays are awaited for
the new hole drilled below GCHR 298

GCHR314 was drilled to test up-dip extensions of the deeper intercept in GCHR298. Resource blocks created by these new intersections are likely to support the mining of the deeper mineralisation defined by GCHR298 in the next round of pit optimisations.

At the south end of the project area, at Wattle Hill, assay results from PQ core hole GCHR315 have been received. At a 0.2% copper cut-off the hole intersected 21 metres @ 0.3% copper, 0.32 g/t gold from 37 metres, 3 metres @ 2.48% copper, 2.36 g/t gold from 82 metres & 25 metres @ 0.26% copper from 105 metres

GCHR315 was drilled as a "scissor-hole" to drill hole CHM18 and to provide metallurgical material from the gold-rich Wattle Hill zone, which is located 500m southeast along strike from the main Copper Hill deposit (Figure 5).

Fig 5: Location on Photo showing Copper Hill and Wattle Hill
(Optimised pit boundaries shown in red)

GCHR315 confirms and extends the intercepts in drill hole CHM18 of 26 metres @ 0.5g/t gold from 2 metres and 20 metres @ 0.32g/t gold from 74 metres. (Figure 6)

More assays are expected in due course, from the last 60 metres of GCHR315.
The 3m high grade intercept of 2.48% copper at 82 metres down-hole may correlate with the zone of 8m @ 3.72% copper in GCHR249, located 100m northwest on section 4500N. If this interpretation is correct, this zone may plunge further towards and beneath Copper Hill. Insufficient drilling has been completed at depth in this part of the deposit creating the possibility that narrow, but strike extensive zones of +1% copper could lie between Wattle Hill and extend beneath the current optimised Copper Hill open pit.

Further evidence for this is provided by the intersection in core hole MEXCHD01 on section 4700N of 73 metres @ 0.45% copper and 0.42g/t gold from 263 metres down-hole. This is currently interpreted to represent a northwesterly plunge of shallower higher grade mineralisation 100 metres to the southeast. These up-plunge intersections, of 23 metres @ 0.6% copper and 0.8 g/t gold and 60 metres @ 0.48% copper and 0.85g/t gold, give good indications of the potential to be realised at Wattle Hill and beneath the current defined resource at Copper Hill.

Previous drilling at Wattle Hill left open zones of mineralisation, and further drilling is planned to test for more extensions. Results to date confirm higher than average resource grade mineralisation extending from 4200N to 4700N, a strike distance of over 500 metres. The results from GCHR315 are anticipated to have a positive impact on pit optimisation by introducing higher grade blocks in an area currently modelled as Inferred and low grade. Further drilling is underway, with 8,500 metres more planned at Wattle Hill, Copper Hill and at Buckley's Hill in the next three months.

Fig 6: Section 4400N at Wattle Hill showing extensions
to mineralisation from hole CHM18

Copper Hill Resource Estimate Reminder
535,000 tonnes of copper and 1.47 million ounces of gold
contained within
173 million tonnes at 0.31 percent copper and 0.26 grams per tonne gold

Outcropping Hill - Open Pit Planned - Railway to Site - Water Sites Identified - Molong Support
Proximity to Power - Feasibility Study Advanced- 2 Rigs now on Site

Compliance Statements
The information in this report that relates to Exploration Results is based on information compiled by Kim Stanton-Cook, who is a member of the Australian Institute of Geoscientists, is a full-time employee of GCR, and has sufficient experience relevant to the style of mineralisation and type of deposit under consideration and to the activity 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". Kim consents to the inclusion in the report of the matters based on this information in the form and context in which it appears

Samples for assay were obtained from half sawn PQ and HQ drill core. Analyses were undertaken at ALS Orange using 50g Fire Assay (Method AA26) for gold and ICP41 for copper and a suite of other elements. Standards and blanks were inserted into the sample stream at regular intervals.

Intercepts have been calculated using a 0.2% copper cut-off with maximum internal dilution of 3 metres [*except for the intercept in GCHR315 from 105m which has internal dilution of 6m]

The Resource Estimates were performed by Dr Phillip Hellman, a Director of Hellman & Schofield, Consulting Geologists and specialists in resource estimation and geostatistics. Dr Hellman is a Fellow of the Australian Institute of Geoscientists (AIG), has more than five years experience in the field of activity in which he is reporting and consents to his report being incorporated into this announcement in the context in which it appears above.

The Copper Hill Resource is classified as shown below:

Note: The Measured, Indicated and Inferred Resource Estimates are reported under the
2004 JORC Code and Guidelines. Search parameters for the categories are as follows:
Measured = 40m x 45m x40m (min 12 data points);
Indicated = 60m x 65m x 60m (min 10 data points);
Inferred = 100m x 110m x 100 (min 6 data points)

 

Figure 7: Copper Hill - Aerial view from North showing Mitchell Highway,
existing railway line and the town of Molong in the middle distance.


February 2011

 

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