Avesoro Resources Regulatory News (ASO)

20 May 2013

Aureus Mining Inc.

TSX : AUE

AIM : AUE

NEW LIBERTY OPTIMISED DFS CONFIRMS STRONG FINANCIAL RETURNS

Aureus Mining Inc. ("Aureus" or the "Company") is pleased to announce its NI 43-101 compliant optimised Definitive Feasibility Study ("DFS") for its 100 % owned New Liberty Gold Project in Liberia ("New Liberty" or "the Project") following the completion of the optimisation work which focused on the plant and mine designs and the location of site infrastructure. The DFS outlines an economically robust gold project based on a flat gold price of US$ 1,400 / oz - moreover, the Project has been extensively de-risked from design, operational and environmental perspectives. Capital and operating costs are estimated to a higher level of accuracy. The DFS has increased the average production profile for the first six years. New Liberty will be Liberia's first commercial gold mine and Aureus' first mine in its highly prospective 546 km2 total licence area.

Key highlights of the DFS and work completed to date include:

·; Independent NI 43-101 compliant DFS confirms a technically feasible and economically robust project, with the following attractive economics based on a discount rate of 5%:

·; Average annual gold production of 119,000 ozover the first six years at an average grade of 3.6 g/t with total gold production of 859,000 oz over the eight year, open pit, life of mine ("LOM"). 1.5% increase in total production with an increase production rate over the first 6 years

·; LOM operating cash cost will average US$ 668 / oz using contract mining, a reduction of 2.5%

·; Initial capital cost estimate of US$ 136 million (excluding contingency), a reduction of 2.9%

·; Total revenue is US$ 1.2billion and pre-tax cash flow of US$ 353 million using a flat gold price of US$ 1,400 / oz

·; Proven and Probable Reserve of 8.5 Mt at 3.4 g/t for 924 koz of contained gold, an increase of 1.6%

·; Optimisation work resulted in the relocation of the Tailings Storage Facility ("TSF") area and plant to more central positions south of the pit and away from the stream diversion. The TSF now locates in a natural topographic bowl and requires only one dam wall. The Waste Rock Dumps ("WRD") have been redesigned to locate around the pit and this will assist with mine closure

·; Improvements in the plant design have resulted in significantly lower reagent consumptions and a reduction in the number of CIL tanks. The use of finer grinding and high shear with oxygen will facilitate steady state gold recoveries at an average of 93% for the first six years

·; There is now a higher level of confidence in the mining schedule from the updated geotechnical model and mine designs. With production more evenly distributed over the LOM, the Project has a lower execution risk

·; The relocation of the TSF and plant, redesign of the WRD and the significant reduction in cyanide consumption all mitigate against environmental risks

·; At a flat gold price of US$1,400/oz verses previous gold price assumptions, pre-tax NPV5% increases from US$ 225 million under the Previously Announced Feasibility Study to US$ 230 million under the DFS. Pre tax IRR of 28.5% (previously 32.3%) reflecting more conservative production ramp up schedule for Liberia's first commercial gold mine

·; Plant commissioning and first gold production scheduled for December 2014

·; Owner team in place for the construction of New Liberty

·; 25 year, renewable mineral development agreement and mining licence. All other major permits secured, including environmental, relocation action plan and community development plan

·; Total spend to date on New Liberty is US$ 61 million, including US$ 49 million on exploration and evaluation. US$ 9 million of the total US$ 136 million capital cost has been incurred to date on early earthworks (including clearing the creek diversion and plant site), site road re-grading (20 km), installing bridges and EPCM project services

·; The cash position as at 31 March 2013 is US$ 68.9 million

·; Bank project finance process continuing with credit committee approval expected in late Q2 or early Q3 2013

David Reading, Chief Executive Officer of Aureus, commented:

"We are pleased with the results of the optimisation studies and the completion of the DFS. This work has improved the project in terms of mining and plant designs and the layout of the waste and plant infrastructure. The work has now been completed to a greater level of detail than in the previously published study and the Company feels that the overall result is a project that is significantly de-risked with an optimum design, resulting in lower cash costs as well as lower capital expenditure for the building of the mine. New Liberty is a robust and very competitive West African project due to its cash operating costs, a modest capital outlay, excellent grade and rapid return on investment criteria. The New Liberty project is an excellent first step in developing Liberia's nascent gold mining industry."

"Whilst completing the detailed optimisation work, our development teams have completed earthworks at the plant, tailings and stream diversion sites. We have also ordered the ball mill and are currently in the process of relocating the Larjor and Kinjor villages. The Company remains on track for the first gold pour in December 2014. Our focus is now exclusively directed to completing the debt financing process and commencing civil construction after the rainy season in Q3 2013."

"On the exploration front we have completed drilling programmes at Weaju and Ndablama and await further assay results. Our generative team has completed geochemical coverage of the whole licence portfolio and we are continuing to assess a number of potential new gold targets. We are very excited about the potential of our exploration portfolio and committed to unlocking further value through resource expansion and the development of additional mining projects."

There will be a conference call hosted by David Reading on Monday 20 May 2013 at 09.30 BST to discuss the DFS.

Participants may join the call by dialling one of the following numbers approximately 10 minutes before the start of the call:

UK (toll free): 0808 238 0673

Rest of the world: +44 1452 569 335

Participant pass code: 70708063

A separate conference call will be held for Canadian analysts and investors on 21 May at 09:30 EDT / 14:30 BST

Participants may join the call by dialling one of the following numbers approximately 10 minutes before the start of the call:

Canada (toll free): +1 866 494 9885

Rest of the world: +44 1452 569 335

Participant pass code: 71220566

Optimisation Work

The DFS has been prepared based on the optimisation work which updates the Feasibility Study published on 1 October 2012 (the "Previously Announced Feasibility Study"). The optimisation work focused on three specific areas, plant, mining and infrastructure, with the intention of reducing capital and operating costs and improving operating conditions, without compromising safety.

Plant

·; Relocation of process plant to the south of the pit and more central to the ore body and the WRD. The new plant location is now much closer to the new TSF location which reduces pumping costs. The closer proximity of the open pit results in reduced haulage distances. The plant is now located on a 4° slope and this slope assists in reducing conveyor distances and therefore power consumption. The close proximity of the plant to the TSF and the incorporation of a raw water storage pond will enable plant water to be recycled during processing.

·; Reduction in reagent consumption and optimisation of gold recovery. ALS Laboratories ("ALS"), on behalf of DRA Mineral Projects (Pty) Ltd ("DRA"), conducted additional metallurgical studies, including work on improving the leach kinetics and the application of high shear pre-oxidation oxygen and some finer grinding. As a result of this work, cyanide consumption is reduced by 66% and the CIL leach residence time is halved from 48 to 24 hours. This work led to the reduction in CIL tanks by two and the elimination of one of the larger pre-oxidation tanks.

·; Metallurgical testwork confirms an average 93% steady state recovery. This recovery rate for the first six years and 90% in the last two years as the grade drops off to below 2.5 g/t to reflect lower grade stockpiles treated at the end of the mine life.

·; The plant layout is now more optimally configured. It is more compact and will be easier to operate. Opportunities still remain for the installation of an additional ball mill and CIL tanks.

Mining

·; The pit design and mining schedules have been refined to a higher level of confidence. As a result of the inclusion of substantial additional data, a new geotechnical model has been developed and pit slope designs parameters have now been outlined in more detail with specific domains defined.

·; Accommodating for high seasonal rainfall. Safety berms have been enhanced and drainage capacity and pump capacity have been improved.

·; Revised designs and pit designs.  This results in a Mining Reserve contained ounce increase of approximately 1.5% and the average gold grade increasing from 3.3 to 3.4 g/t.

·; Mining fleet will be new. This reduces the operating risk and has less maintenance requirements and standing time and should improve reliability (Previously Announced Feasibility Study had a mixed fleet of new and used machines).

·; Mining vertical rates of advance were reviewed. These are more conservative and take into account the local climate and operating conditions.

Infrastructure:

·; Relocation of TSF to the south of the pit. This re-siting reduces the environmental risk as it removes the requirement to have a tailings pipe from the plant to the TSF that crosses the Marvoe Creek Diversion Channel ("MCDC").

·; The TSF is located in a natural topographic bowl. This site only requires the construction of one dam wall.

·; Proximity of TSF to plant site will reduce pumping costs.  The TSF is now closer to and is down-slope from the process plant, thereby reducing pumping costs.

·; TSF design incorporates a raw water storage pond to facilitate recycling of plant water.

·; Relocation of WRD. The WRD now wrap around the pit in all directions to reduce haulage costs and provide additional protection against any risk of flooding. The WRD now have a lower height profile which will reduce the rehabilitation requirements.

·; LiDAR survey (Light Detection and Ranging - airborne laser survey technique) identified a more suitable route for the MCDC. This survey facilitates the reduction of volume of earthworks being undertaken.

The optimisation work has resulted in the Project having an optimal layout and design which has reduced the technical, environmental and operational risk.

Work on the DFS commenced in October 2012 and Aureus was assisted by AMC Consultants Pty Ltd ("AMC") and DRA.

Comparison of DFS and Previously Announced Feasibility Study

The key Project parameters comparing the DFS to the Previously Announced Feasibility Study can be summarised as follows:

Note * - Previously Announced Feasibility Study numbers use the DFS gold price of US$ 1,400 / oz flat for comparative purposes

The DFS compares very favourably with the Previously Announced Feasibility Study as it has demonstrated the robustness of the Project, reduced the execution risk for the construction phase and also lowered the operating cash cost by 2.5 %. The gold price assumption used in the DFS has been updated from an average of US$ 1,400 / oz as used in the Previously Announced Feasibility Study to US$ 1,400 / oz flat as a consequence of the recent reduction in the gold price.

DFS study

The NI 43-101 compliant DFS for the New Liberty Gold Project summarises the Reserves, mining and mine production schedule, metallurgy, process plant design, infrastructure design, including tailings management facility, capital and operating cost estimates and financial modelling. Mining design and scheduling, pit water management and the WRD design have all been undertaken by AMC. DRA are responsible for all process design, infrastructure design and metallurgical testwork. The environmental studies were previously outlined by Golders in the Previously Announced Feasibility Study announced on 1 October 2012 and are now being updated by Digby Wells (Pty) Ltd ("Digby Wells").

Reserve Statement

The updated Reserve statement for the NI 43-101 compliant DFS for the New Liberty Gold Project has been based on the Resource statement that was previously announced on 1 October 2012 in the Previously Announced Feasibility Study. The updated Reserve statement has been compiled by AMC with contributions from DRA for metallurgical recovery and processing costs and initial capital numbers. The Reserve estimate was undertaken by AMC in accordance with the requirements of NI 43-101.

The total Reserve estimate of 923,716 oz of gold grading 3.4 g/t is comprised of 704,600 tonnes grading 4.4 g/t (for 99,470 oz) in the Proven category and 7,789,500 tonnes grading 3.3 g/t (for 824,246 oz) in the Probable category, as detailed in the table below. This represents an increase of 1.6% (14,478 oz) in the total Reserve in comparison to the Reserve statement as at 1 October 2012. The Proven and Probable Ore Reserves are contained within open pits of depths between 180 and 220 metres below surface. The ore body is still open at depth and to the west.

The reported Reserve estimate is shown in the following table:

Notes:

1. The Ore Reserve was estimated by construction of a block model within constraining wireframes and based on Measured and Indicated Resources

2. The Ore Reserve is reported at a cut-off grade of 0.8 g/t Au and ore grading between 0.8 and 1.0 g/t cut-off is stockpiled for processing towards the end of the mine life

3. A dilution skin of 0.5 m added and a minimum mining width of 2.5 m was applied

4. The Ore Reserves were estimated based on the updated NI 43-101 Mineral Resource as stated in this same study

5. The cut-off grade of 0.80 g/t was used for pit optimisations and were based on a gold price of US$ 1,300 / oz

6. A 93 % metallurgical gold recovery was used

7. Due to rounding, some columns or rows may not add up exactly to the computed totals

The Reserve supports an open pit operation with an average annual production rate of 1.1 Mtpa of ore over an eight year production life. The mining schedule sees the operation produce a total of 8.5 Mt of ore grading 3.4 g/t with an associated 131 Mt of waste with an average life of mine stripping ratio of 15.5 times over a mine schedule of 8 years - the plant is scheduled to produce an average of 107,000 oz per annum at a grade of 3.4 g/t over the production life, with an average of 119,000 ounces per annum in the first six years of production.

The open pit will comprise three adjacent and interconnecting pits. All of the Reserve at New Liberty is located within 220 meters of surface and is extractable by open pit mining methods.

A steady state mining rate is planned after the initial period of waste pre-stripping at an annualised plant feed rate of 1.1 Mt. The annual waste mining rate is 25.9 Mt for the first 4 years followed by 6.4 Mt for the last 4 years, which results in an average annual waste mining rate of 16.2 Mt over the 8 year mine life. It is planned to pre-strip an estimated 2.5 Mt of waste and 0.3 Mt of ore at a cost of US$ 6.3 million, which is included in the initial mine capital cost budget. The waste material will be dumped in the WRD which wraps around the pit and also as backfill into the Larjor pit. A mining contractor will be used for all earthmoving activities and mining operations will use a conventional truck and shovel method.

The mine design aspects were completed by AMC and comprised pit optimisation using Whittle-4X based on the Measured and Indicated Resources. The optimised pit design and schedule are refinements of those developed for the Previously Announced Feasibility Study. A staged mining sequence was developed for production scheduling.

Key Project Parameters

The key technical, operational and financial information has been summarised in the following table:

Infrastructure and Capital Costs

The initial capital cost of US$ 136 million for the project (excluding contingency) includes the design and development of the processing plant, mining establishment and pre-strip, general mine infrastructure and power supply, tailings dam construction, creek diversion and general infrastructure.

Capital costs are summarised as follows:

Deferred capex will be incurred following the commencement of production and is included within the modelling and financial parameters as presented. Sustaining capex includes the mine closure costs, which includes the costs in relation to the environmental aspects at the mine and process plant sites. Mining operations will be undertaken on a contract basis. As in the Previously Announced Feasibility Study, the gensets, fuel farm and mining fleet equipment are covered by lease agreements over the LOM.

Operating Cash Costs

Note, operating cash costs exclude costs for freight and refining and government royalties

The financial model, which includes all of the capital and operating costs, has been prepared based on capital and operating cost estimates and production schedules provided by and endorsed by competent persons.

Economic Sensitivity Analysis

The economic analysis was undertaken on a pre-tax basis and pre Government free and carried interest and utilises a flat gold price of US$ 1,400/oz over the eight year life. This data is presented with a sensitivity analysis which examines the project economics at flat gold prices (stated in US$ / oz).

The Government of Liberia ("GOL") corporation tax is 30% and the net smelter royalty is 3%. The GOL holds a 10% free and carried interest in the project which is payable after all capital cost and project sunk costs have been recovered. The total spend to date on New Liberty is estimated to be US$ 61 million.

A sensitivity analysis was undertaken on the project economics and the results are set out below:

General Infrastructure Layout

The overall New Liberty mining project covers an area of 33 km2 and includes process plant, offices, workshops, generator power plant, housing and warehouses, mining camp, a TSF, a WRD, explosives bay, various ore stockpiles and a creek diversion ("MCDC").

The TSF and MCDC design work was undertaken by DRA. The TSF covers an estimated footprint of 78 hectares and locates in a naturally occurring topographic bowl to the south of the plant site. The TSF requires one dam wall which will be constructed before production commences (and is included in the initial mine capital cost budget). The total dam capacity will provide for the storage of 9.7 million tonnes of processed material. The MCDC design results in the diversion of a small river channel to the North and West of the open pit area. The diversion channel will consist of a series of interconnecting excavated channels, small dams and berms. The clearing work for the MCDC has been completed and preparations are underway for the excavation works. The diversion channel will be completed during 2013 with the channel being diverted before the commencement of the pre-strip earthmoving in 2014.

Plant Process Design

The plant design is based on a typical two-stage crushing process, milling and CIL (it includes primary crushing, secondary crushing and a primary ball mill with a secondary regrind mill). A gravity circuit will be used on the primary cyclone underflow stream to recover free gold from the recirculating load in the milling circuit. The gravity concentrate will be leached in a reactor and the gold will be recovered from the pregnant solution with electro-winning. The milled product will gravitate to a trash screen before entering a pre-leach thickener. Thickened underflow will be pumped to a pre-oxidation stage using a shear reactor which flows into a six stage CIL to recover the dissolved gold onto carbon. Loaded carbon will be stripped in the elution and the eluate will be subjected to electrowinning to recover the gold. Loaded cathodes will be washed and the resultant gold sludge will be smelted to doré in a conventional gold room. Cyanide in the CIL tailings along with any other impurities will be detoxified in three stages prior to discharge to the TSF.

In the optimised flow sheet for New Liberty, high shear oxygen addition has been added to the pre-oxidation tank and the leach tanks have been removed. The CIL circuit has been re-sized to allow for a 24 hour residence time with six stages. The optimized circuit also includes second stage cycloning and a regrind mill.

A high proportion of the contained gold (50%) is recoverable by gravity with the remaining portion recovered by CIL leach for an overall gold recovery of 93%.

The process flow sheet is well known in the gold mining industry and historically has proven a successful processing route for gold ore bodies in Africa.

Technical Report

Aureus will file a NI 43-101 compliant technical report on the New Liberty Project outlining the Mineral Resources and Reserves Estimate and the results of the DFS. The report will be available within 45 days at www.sedar.com and on the Company's corporate website www.aureus-mining.com.

Qualified Persons

The Reserve Study was prepared by Martin W Staples BSc (Mining Engineering), FAusIMM of AMC. Mr Staples is a Qualified Persons, for the purposes of the study, under the standards set forth by National Instrument 43-101 "Standards of Disclosure for Mineral Project", of the Canadian Securities Administrators ("NI 43-101"), and he has reviewed and approved the contents of this news release, as applicable.

The design and capital estimate to DFS level of the processing plant and associated infrastructure, mining support infrastructure, incorporating capital estimates for the MCDC and the TSF, was undertaken by DRA Mineral Projects under the supervision of Robin M Welsh, BSc Engineering, Pr Eng, MSAIEE. Mr Welsh has reviewed and approved the contents of this news release, as applicable.

The basic process plant configuration and recovery were prepared by Mr Glenn Bezuidenhout of DRA Mineral Projects. Mr Bezuidenhout is a Fellow of SAIMM, and has sufficient experience, which is relevant to the style of mineralization and type of deposit under consideration, and to the activity which he is undertaking to qualify as a Competent Person as defined by the NI-43-101. Mr Bezuidenhout has reviewed and approved the contents of this news release, as applicable.

Contact Information

About Aureus Mining Inc.

The Company's assets include the New Liberty gold deposit in Liberia (the "New Liberty Gold Project" or the "Project"), which has an estimated proven and probable reserve of 924,000 ounces of gold grading 3.4 g/t and an estimated measured and indicated mineral resource of 1,143,000 ounces of gold grading 3.63 g/t and an estimated inferred mineral resource of 593,000 ounces of gold grading 3.2 g/t. A Definitive Feasibility Study has been completed on the Project and construction has commenced with initial earthworks. The Project is expected to have an 8 year mine life and annual production of 119,000 ounces for the first 6 years of production. The Company has financed the Project's equity funding requirement and has mandated two banks for the remaining debt balance.

The New Liberty Gold Project is located within the Bea Mountain mining licence, which covers 457 km² and has a 25 year, renewable, mineral development agreement. The Bea Mountain mining license also hosts the proximal gold targets of Ndablama, Gondoja and Weaju, which are the focus of exploration programs during 2013. The contiguous Archaen Gold exploration licence, which covers 89 km², is also a focus of exploration for 2013, with Leopard Rock being the main target.

The Company also has gold exploration permits in Cameroon.

Forward-looking Statements 

This press release contains certain forward-looking information. All information, other than information regarding historical fact, that addresses activities, events or developments that Aureus Mining believes, expects or anticipates will or may occur in the future is forward-looking information. Forward-looking information contained in this press release includes, but may not be limited to, the future plans and objectives of Aureus Mining and their anticipated future growth, mineral resource estimates and the anticipated exploration and development activities of Aureus Mining. The foregoing and any other forward-looking information contained in this press release reflects the current expectations, assumptions or beliefs of Aureus Mining based on information currently available to Aureus Mining. With respect to the forward-looking information contained in this press release, Aureus Mining has made assumptions regarding, among other things: general business, economic and mining industry conditions; and it has also been assumed that no material adverse change in the price of precious and/or base metals occurs, no unusual geological or technical problems occur and no significant events occur outside of the normal course of Aureus Mining's respective business.

Such forward-looking information is subject to a number of risks and uncertainties that may cause actual results or events to differ materially from current expectations, including: risks normally incidental to exploration and development of mineral properties; uncertainties in the interpretation of results from drilling and test work; the possibility that future exploration, development or mining results will not be consistent with expectations; uncertainty of mineral resources estimates; adverse changes in precious and/or base metal prices; and future unforeseen liabilities and other factors including, but not limited to, those listed under "Risk Factors" in the Preliminary Prospectus of Aureus Mining Inc. dated April 20, 2011 a copy of which is available on SEDAR at www.sedar.com, and in the Aureus Mining Admission Document, a copy of which is available at www.aureus-mining.com.

Any mineral resource figures referred to in this press release are estimates and no assurances can be given that the indicated levels of minerals will be produced. Such estimates are expressions of judgment based on knowledge, mining experience, analysis of drilling results and industry practices. Valid estimates made at a given time may significantly change when new information becomes available. While Aureus Mining believes that the mineral resource estimates in respect of their respective properties are well established, by their nature mineral resource estimates are imprecise and depend, to a certain extent, upon statistical inferences which may ultimately prove unreliable. If such mineral resource estimates are inaccurate or are reduced in the future, this could have a material adverse impact on Aureus Mining, as applicable. Due to the uncertainty that may be attached to inferred mineral resources, it cannot be assumed that all or any part of an inferred mineral resource will be upgraded to an indicated or measured mineral resource as a result of continued exploration.

Forward-looking information speaks only as of the date on which it is made and, except as may be required by applicable law, Aureus Mining disclaims any obligation to update or modify such forward-looking information, either as a result of new information, future events or for any other reason.