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1 December 2008            

RUSINA MINING NL ('Rusina' or the 'Company')

The following announcement replaces the announcement made on 27 November 2008 at 12.35 with RNS number 0870J and now includes a full glossary of terms, set out at the end of this announcement. Please note that no other changes have been made to the text of the previous announcement. 

Rusina Announce Positive Results on the Acoje Pre-Feasibility Study in the Philippines - Replacement

Highlights

• JORC combined limonite plus saprolite Indicated Resource of 34.41 Mt at 1.09% nickel from an Inferred plus Indicated Resource of 50.14 Mt at 1.06% nickel using a 0.8% cut off grade

• Estimated annual production of 24,500 tonnes of nickel and 930 tonnes of cobalt

• Estimated cash cost of US$3.10/lb of nickel, net of by-products including refining costs at US$6.00/lb nickel price and US$10/lb cobalt price

• Total development estimated at US$498 million

• Estimated capital cost per annual pound of nickel of US$7.84

• Post-tax Net Present Value of US$375 million (at a 10% discount rate) and US$6/lb nickel price and $10/lb cobalt

• Internal Rate of Return of 28.3%

• 3 year payback period

• Forecast annual sales of US$260 million, based on a long term nickel price of US$6.00/lb and including by-product credits

• Significant potential to increase NPV and IRR with extended mine life by confirming the JORC Inferred Acoje and Zambales Chromite deposits to JORC Indicated status

 

Rusina Mining (AIM:RMLA, ASX:RML) is pleased to announce positive results from the pre-feasibility study on the Acoje deposit in the Philippines using European Nickel's heap leach technology. European Nickel and Rusina will now commence a Definitive Feasibility Study ('DFS'), which will be due for completion by late 2009.

The pre-feasibility study results demonstrate an economically viable nickel laterite project using heap leach technology producing 24,500 tonnes a year of contained nickel and 930 tonnes of contained cobalt. The study for the Acoje project is based on a JORC Indicated Resource of 30.76 million tonnes at 1.12% nickel and 0.05% cobalt (at a 0.8% nickel cut-off for saprolite and a 0.9% nickel cut off for limonite) giving the project an initial mine life of ten years. Mining will be at a rate of three million tonnes per annum, with a low strip ratio of 0.46, and cash costs are estimated at US$3.10 per pound of nickel (at US$6/lb Ni), net of by-products including a refining charge of 25% of the nickel price and a cobalt price of US$10/lb. Further potential resources have been identified, the JORC Inferred Resources at Acoje and the Zambales Chromite deposit, which are expected to extend the mine life beyond 20 years and are expected to be confirmed to JORC Indicated Resource levels during the DFS.  

The basis for the Study was the November 2008 Snowden Mining Industry Consultants (Snowden) resource estimate. The Companies anticipate that further resources will be upgraded at Acoje by infill drilling in 2009.  This could significantly increase the net present value and the rate of return of the project in the future.

It is proposed that the nickel laterite ore will be leached with dilute sulphuric acid produced from a sulphur burning acid plant to be built at the site and the nickel will be recovered in a precipitation plant in a two stage concentration process producing two saleable products. The first stage primary nickel product ('PNP') will contain 39% nickel and 1% cobalt and the second stage nickel product (SNP) will contain 25% nickel and 1% cobalt. The project plans to use the same plant design as European Nickel's Çaldağ project in Turkey where over 80% of the design for the precipitation plant is already complete. 

The Acoje project's total development cost is estimated at US$498 million, including infrastructure and working capital, which equates to a capital cost per annual pound of nickel of US$7.76. The project has a post-tax Net Present Value of US$375 million (at a 10% discount rate), an Internal Rate of Return of 28.3% and a three year payback period. Annual sales, based on a long term nickel price of US$6.00 per pound, are forecast at US$260 million, including by-product credits which would generate US$108 million of free cash flow annually.

European Nickel will, pursuant to the terms of the joint venture, earn a 40% economic interest in the Acoje deposit by spending US$10 million on the metallurgical heap leach trial, engineering design and permitting, following which Rusina will hold 40% and their Philippine partner, DMCI Mining Inc, will hold 20%.

The potential development and commercial mining operation at Acoje will have a significant positive economic impact on the local and regional community.  During the development and construction phase, approximately 50% of the construction costs are estimated to be spent within the Zambales region and of the US$498 million total development cost, an estimated 70% will be expensed in the Philippines. This project will provide a significant economic and social boost to the Zambales region.

A copy of the Executive Summary of the Pre-Feasibility Study is available on the Company's website - www.rusina.com.au.

Resource Model

Based on additional geological modelling in 2008, the Companies updated the first JORC-Compliant resource estimate produced for Acoje by SRK Consulting (SRK) in December 2007, with a second resource produced by Snowden in November 2008. The Companies prepared the electronic database which was then reviewed by Snowden. The JORC-compliant resource estimate (including Indicated and Inferred resources) for limonite and saprolite, produced by Snowden at a 0.8% nickel cut-off was 50.14 Mt @ 1.06% Ni which includes approximately 233,000 tonnes @ 1.44% nickel that has already been mined.

The new updated resource estimate is the result of 3 dimensional block modelling undertaken by Snowden Mining Industry Consultants, Perth (Snowden) for use in producing a mine plan and schedule.

A detailed breakdown of the resource is provided below:

Property	JORC Category	Million Tonnes	Ni (%)	Co (%)
Acoje Limonite	Indicated	10.78	0.99	0.081
	Inferred	5.27	0.93	0.075
Acoje Saprolite	Indicated	23.62	1.14	0.038
	Inferred	10.67	1.05	0.044
Total Acoje*		50.14	1.06	0.052

Cut-off grade Ni = 0.8%

Rounding may introduce minor computational errors 

*includes approximately 233,000 tonnes mined at a grade of 1.44% Ni

Resource Details

The resource estimate was undertaken independently by Snowden. The resource for the Acoje Nickel Laterite has been re-estimated, using all drill holes and test pits available as at 31 May 2008. The estimate is based on 1,587 drill holes and test pits, spaced on a nominal 100m x 100m grid and in some cases closer. Each pit was manually sampled on 1m intervals, and each diamond drill core was split in half and sampled on 1m intervals. All samples were split at site, with one sample being kept at Rusina's storage facility. All samples were assayed at McPhar Assay Laboratories in Manila using chemical digestion for Cr2O3, Ni, Cu, Co, Fe, Mg and fire assay for Au, Pd, Pt. The sample database was reviewed and checks were conducted to identify entry errors. Where pits were twinned by a deeper drill hole Snowden elected to use the deeper information for model construction and resource estimation.

A geological model of the laterite deposit was constructed by Snowden based on the supplied geological rock-type codes and chemistry of the sample assay data. The geological model identifies soil (overburden), limonite and saprolite horizons. MgO/Fe ratios were used to define limonite, saprolite and bedrock rock-type codes. Soil (and unmineralised overburden) was defined as material <0.60% Ni from surface. Snowden generated base of overburden, limonite, and saprolite horizon surfaces by first estimating thickness models for each horizon in 2D and then by subtraction from the topographical surface dxf, a set of 3D surfaces (wireframes) were constructed.  

After checking whether compositing was required, the data was 'unwrinkled' within the limonite, saprolite and bedrock horizons for statistical, variogram analyses and grade interpolation. Statistical analysis was undertaken on the Ni, Co, SiO2, MgO, FeO and Cr2O3 data from within the modelled limonite, saprolite and bedrock horizons and Snowden elected to apply top-cuts to Ni (saprolite only), Co and Cr2O3 (limonite), SiO2 (limonite) to restrict the influence of outlier values.

Block grades for Ni, Co, SiO2, MgO, FeO and Cr2O3 were estimated into percent volume models for the limonite and saprolite horizons separately using ordinary kriging in Gemcom mining software. The horizon surfaces were regarded as 'hard' boundaries for the purposes of grade estimation and thus only samples coded for each horizon were used for grade estimation within each horizon. Block grades (including 0.45% Ni and 0.057% Co) were assigned to the overburden horizon, based on the mean grade of the data from within this horizon. 

Bulk density factors agreed with European Nickel of 1.0, 1.5, 1.6 t/m3 were assigned to the overburden, limonite, and saprolite horizons respectively. The limonite and saprolite density factors are supported by Rusina supplied density measurements.

A regularised block model with a block size of 25 mE by 25 mN by 3 mRL (elevation) was developed using the block proportion, grades and densities from within each horizon.

The Acoje Mineral Resource estimate block model has been classified as Inferred and Indicated. The sample methods, assay quality and sample spacing together with confidence in the geological interpretation have been considered in application of the resource categories of Inferred and Indicated to the block model.  

This information related to resources in this press release has been compiled by Mr. H. Andrew Daniels, P. Geo Consulting Geologist and Exploration Manager to European Nickel PLC from the Snowden 2008 Acoje Resource Update. Mr. Daniels is both a Qualified Person as defined in NI 43-101 and Competent Person under the JORC and SAMREC codes, respectively. Mr Daniels has sufficient experience which is relevant to the style of mineralization and type of deposit under consideration and to the activity which has been undertaken to qualify as a Competent Person under the JORC Code and SAMREC Code respectively. Mr. Daniels consents to the inclusion in this report of the matters based on their respective information in the form and context in which it appears.

For more information, please contact:

Rob Gregory, Rusina Mining Tel: +61 8 9226 1111/ +63 2 815 1656 W: www.rusina.com.au Mark Hanlon, Rusina Mining Tel: +61 8 9226 1111 W: www.rusina.com.au Kevin Skinner, Field Public Relations Tel: +61 8 8234 9555

Glossary of Terms

Block modelling	Block modelling is a technique which models mineral deposits as a set of 3-D cells and sub-cells. Models may represent geological structure, or grade distribution, or both. There is a choice of interpolation methods, statistical and geostatistical, and the model can be edited and examined interactively in plan or section.
By-product credits	By-product credits represent the net cash benefit received from the sale of secondary products realised through the processing of the primary product
Co	Chemical symbol for cobalt
Compositing	compositing is the combining of visual elements from separate sources into single images
Cr2O3	Chemical symbol for chromite
Cu	Chemical symbol for copper
Cut-off grade	The lowest grade, or quality, of mineralised material that qualifies as economically mineable and available in a given deposit. May be defined on the basis of economic evaluation, or on physical or chemical attributes that define an acceptable product specification.
Dxf	Dxf means Drawing Exchange Format and is a computer-aided design data file format for enabling data interoperability between AutoCAD and other programs.
Fe	Chemical symbol for iron
FeO	Chemical symbol for iron oxide
Heap leach	The process whereby mined nickel laterite ore is heaped on an impermeable plastic and/or clay lined leach pad where it can be irrigated with a leach solution to dissolve the nickel metal. Sprinklers, or often drip irrigation, are used to minimize evaporation. The solution then percolates through the heap and leaches out the nickel metal. The leach solution containing the dissolved metals is then collected and recovered through a precipitation plant.
Infill drilling	The process of drilling between current drill holes to achieve a higher density of drill holes and thus greater geological certainty
Inferred	An 'Inferred Mineral Resource' is that part of a Mineral Resource for which tonnage, grade and mineral content can be estimated with a low level of confidence. It is inferred from geological evidence and assumed but not verified geological and/or grade continuity. It is based on information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that may be limited or of uncertain quality and reliability.
Indicated	An 'Indicated Mineral Resource' is that part of a Mineral Resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a reasonable level of confidence. It is based on exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes. The locations are too widely or in appropriately spaced to confirm geological and/or grade continuity but are spaced closely enough for continuity to be assumed.
JORC	The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves, 2004 (the 'JORC Code' or 'the Code'). The Code sets out minimum standards, recommendations and guidelines for Public Reporting in Australasia of Exploration Results, Mineral Resources and Ore Reserves. The definitions in the JORC Code are either identical to, or not materially different from, those similar codes, guidelines and standards published and adopted by the relevant professional bodies in Australia, Canada, South Africa, USA, UK, Ireland and many countries in Europe.
Limonite	Any of a group of widely occurring yellowish-brown to black iron oxide minerals used as a minor ore of iron. Limonite nickel laterite ore is characterised by having a higher Fe content and lower Ni content than the lower saprolite zone.
Leached	The removal of elements from a soil by dissolution in liquid moving downward in the ground.
Mg	Chemical symbol for magnesium
MgO	Chemical symbol for magnesium oxide
Mt	Million tonnes
Ni	Chemical symbol for nickel
Ordinary Kriging	Ordinary kriging is a geostatistical approach to modelling that relies on the spatial correlation structure of the data to determine the weighting values. This is a more rigorous approach to modelling, as correlation between data points determines the estimated value at an unsampled point.
Pd	Chemical symbol for palladium
Pre-feasibility study	A comprehensive study of the viability of a mineral project that has advanced to a stage where the mining method, in the case of underground mining, or the pit configuration, in the case of an open pit, has been established, and where an effective method of mineral processing has been determined. This study must include a financial analysis based on reasonable assumptions of technical, engineering, operating and economic factors and evaluation of other relevant factors which are sufficient for a qualified person acting reasonably, to determine if all or part of the mineral resource may be classified as a mineral reserve.
Pt	Chemical symbol for platinum
Saprolite	Chemically rotted rock in situ. The word is often used for the lower segment of a weathering profile. Saprolite nickel laterite ore is characterised by a low Fe content and higher Ni content than the upper limonite zone.
SiO2	Chemical symbol for silica
Test pits	A survey/sampling technique of the upper soil layer whereby holes approximately 60 centimetres square are manually excavated to a depth of up to 10 meters and soil samples are taken and analysed over the full depth of the pit to determine the mineral content over the entire horizon
Twinning	The process of repeating the sampling of a particular geological horizon by the same or an alternative sampling method to check the results of the first sample.

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