Endeavour Expands Nzema Sulphide Program and Initiates Preliminary Economic Assessment

EDV - Toronto Stock Exchange

EVR - Australian Securities Exchange

MONACO, May 2, 2012 /CNW/ - Endeavour Mining Corporation ("Endeavour") (TSX:EDV, ASX:EVR, OTCQX:EDVMF) is pleased to report the expansion of the sulphide drilling program at its 90% owned Nzema Gold Mine following review of drilling results to date, the delivery of the Conceptual Trade-off Study by AMEC Minproc Limited and initial metallurgical testwork completed at SGS Australia Mineral Services.

Drilling has confirmed the presence of several sulphide ore shoots below the principal oxide pits at the Salman Trend.  Highlights include:

Teberu

• SNRC1415  9 m @ 4.91 g/t Au  from 109 m
• SNRC1416  14 m @ 4.13 g/t Au  from 104 m
• SNRC1416 14 m @ 3.15 g/t Au  from 124 m
• SNRC1451 10 m @ 3.84 g/t Au  from 72 m
• SNRC1478 14 m @ 2.48 g/t Au  from 30 m

Salman North

• SNRC1419 3 m @ 11.52 g/t Au  from 79 m
• SNRC1464 12 m @ 9.67 g/t Au  from 38 m

Nugget Hill

• SNDD1446 10 m @ 3.75 g/t Au  from 108 m
• SNDD1447 16 m @ 2.04 g/t Au  from 62 m

Salman South

• SNRC1378 14 m @ 1.94 g/t Au  from 63 m
• SNRC1474 8 m @ 1.67 g/t Au  from 88 m

On the basis of these encouraging results the Nzema exploration program was expanded to include a larger sulphide drilling program, metallurgical testwork, and completion of a preliminary economic assessment by the end of 2012.  The sulphide gold zones at Salman represent a target that Endeavour believes has the potential to significantly increase production at Nzema.

The testwork will examine process alternatives currently being employed to treat refractory sulphide mineralization within West Africa.  The program budget was expanded from US$2.4 to US$6.4M for 2012 in order to accelerate the drilling and achieve the study objectives.

Sulphide Drilling Program Results

A total of 40 holes totalling 5,174 m have been completed thus far in the 2012 drilling campaign.  Significant results for 2011 and 2012 drill campaigns are provided in Table 1.

RC and diamond drilling has targeted the sulphide zone between Salman North and Salman South (Figure 1).  Drilling traverses were initially spaced at 100 metres to provide systematic coverage of the sulphide zones and to highlight the location of higher grade shoots to a vertical depth of 100 metres.  At Teberu, Salman North and Salman South drilling results demonstrate the existence of wide zones of higher grade mineralization that represent ore shoots plunging shallowly to the south.  Closer-spaced drilling has commenced at the locations of the ore shoots (50 metre by 50 metre grid) to assess continuity and to provide sufficient data for the generation of an inferred resource.

Shallower intercepts of oxide mineralization help to delineate the oxide resources and in a few cases have outlined zones that are not currently included in the resources. In some areas faults, possibly thrusts, have resulted in "doubled-up" portions of the mineralized horizons or have caused gaps or dislocations of an otherwise continuous mineralized body.

Table 1: Significant Intercepts for the Salman Sulphide and Oxide Drilling (Holes in bold are located on Figure 1)

To view Figure 1:  Plan map of the Salman Trend showing areas of Nzema Sulphide drilling program, click here

To view Figure 2:  Teberu 04 cross section 553800N, click here

To view Figure 3: Salman South cross section 551450N, click here

Background of Salman Sulphide Project

The Nzema Mine commenced production in late 2010 based on mineral reserves from the Salman, Anwia and Bokrobo deposits.  The mineral reserve of the Salman Trend comprises oxide and some transitional ore contained within a string of open pits along the 9 kilometre trend that extends from Akango in the north to Salman South.  Although gold mineralization extends without a break from oxide through the transition horizon and into the unoxidized sulphide zone, gold within the sulphide zone is refractory and has a low recovery when treated by the existing conventional 'carbon in leach' plant at Nzema (Direct CIL recoveries ranging from 22.7% to 28.4% in lab testwork). Refractory gold deposits exist at other operations in Ghana and Côte d'Ivoire where the ore is treated using either BIOX or Leachox methods (ultra-fine grinding with intensive oxidation of the flotation concentrates).  The refractory gold mineralization of the Salman Sulphides represents a target that Endeavour believes has the potential to significantly increase production at Nzema.

The lower transitional material has a low recovery with conventional carbon in leach and although it is scheduled to be processed through the Nzema oxide plant it may also be more economically processed with the sulphide material.

Conceptual Trade-off Study

In tandem with the resource drilling program in 2011, Endeavour engaged AMEC Minproc Limited to conduct a Conceptual Trade-off Study on the Nzema sulphide project.  The primary aim of the study was to investigate process options for the sulphide material and to assess the economic viability of the project prior to commitment to a resource definition program to convert the resource to reserve. Two potential process options were considered:

1. Off-site toll treatment of  a sulphide concentrate generated on site, or
2. Construction of a concentrator and BIOX plant on site.

The preliminary flotation testwork indicated that a high gold recovery with a small mass pull could be achieved (approximately 90-95% gold in about 5% mass).  This has obvious benefits in terms of capital and operating costs for subsequent treatment processes.  Assuming around 92% gold recovery by CIL of the oxidized concentrate an overall recovery of approximately 83% is indicated.

Next Steps

The revised 2012 drill program includes 15,800 metres of diamond drilling (with RC pre-collars) plus 2,400 metres of RC drilling.  The program is planned to extend the drill coverage to 150 m vertical in anticipation of generating at least Inferred resources at the three main shoots and extend the delineation of the sulphide resource where possible.

The results of this drill program will be assessed via a Preliminary Economic Assessment prior to commitment to a second drilling program to convert the Inferred resources to Measured and Indicated and progress to a Preliminary Feasibility Study.  Delivery of the Preliminary Economic Assessment is planned for the end of 2012.

Qualified Persons

Adriaan Roux, (Pr.Sci.Nat.), Endeavour's Senior Vice President - Operations, is a Qualified Person under NI 43-101, and has reviewed and approved the technical information related to metallurgy and mining operations in this news release.

Martin Bennett, MAIG, General Manager Exploration is the Qualified Person overseeing Endeavour's exploration projects in Ghana and Liberia and has reviewed and approved this press release.

About Endeavour Mining Corporation

Endeavour is a gold producer delivering growth.  Endeavour owns two gold mines producing approximately 180,000 oz per year in Ghana and Burkina Faso that are generating significant operating cash flows to fund exploration and development growth.  In addition to upside potential at its current operations, Endeavour's gold project in Côte d'Ivoire is ready for construction (mining permit submitted; currently negotiating EPCM contract) for an additional 100,000 oz per year.  Endeavour's strong financial base encourages investments in long-term operational growth, exploration to replace and increase reserves, and funding for acquisitions.

Endeavour Mining Corporation is listed on the TSX (symbol EDV) and ASX (symbol EVR), and also trades on the OTCQX (symbol EDVMF).

On behalf of Endeavour Mining Corporation
Neil Woodyer
Chief Executive Officer

This news release contains "forward-looking statements" including but not limited to, statements with respect to Endeavour's plans and operating performance, the estimation of mineral reserves and resources, the timing and amount of estimated future production, costs of future production, future capital expenditures, and the success of exploration activities. Generally, these forward-looking statements can be identified by the use of forward-looking terminology such as "expects", "expected", "budgeted", "forecasts" and "anticipates". Forward-looking statements, while based on management's best estimates and assumptions, are subject to risks and uncertainties that may cause actual results to be materially different from those expressed or implied by such forward-looking statements, including but not limited to: risks related to the successful integration of acquisitions; risks related to international operations; risks related to general economic conditions and credit availability, actual results of current exploration activities, unanticipated reclamation expenses; changes in project parameters as plans continue to be refined; fluctuations in prices of metals including gold; fluctuations in foreign currency exchange rates, increases in market prices of mining consumables, possible variations in ore reserves, grade or recovery rates; failure of plant, equipment or processes to operate as anticipated; accidents, labour disputes, title disputes, claims and limitations on insurance coverage and other risks of the mining industry; delays in the completion of development or construction activities, changes in national and local government regulation of mining operations, tax rules and regulations, and political and economic developments in countries in which Endeavour operates. Although Endeavour has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. Please refer to Endeavour's most recent Annual Information Form filed under its profile at www.sedar.com for further information respecting the risks affecting Endeavour and its business.

Appendix of intercepts:

SOURCE Endeavour Mining Corporation