TORONTO, ONTARIO--(Marketwire - April 26, 2011) - Eastmain Resources Inc. (News - Market indicators) is pleased to announce an updated mineral resource estimate, prepared in accordance with NI 43-101, for its 100%-owned Eau Claire gold deposit (Clearwater Project), located in James Bay, Québec. The updated resource incorporates over 42,218 metres of drilling completed on the deposit since an earlier NI 43-101 compliant resource published in 2005.

This updated resource indicates that definition drilling completed between 2007 and 2009 has expanded the Eau Claire Deposit and significantly increased the Measured and Indicated gold resources over those which were previously reported in 2005. Deep drilling in 2006 also positively impacted the inferred gold resource.

30 parallel quartz tourmaline veins and schist zones that comprise the Eau Claire Deposit, contain a combined Measured and Indicated Resource of approximately 3,354,000 tonnes with an average grade of 5.39 grams per tonne gold (g/t) for 582,000 ounces gold. In addition, 5,322,000 tonnes with an average grade of 5.96 g/t gold, classified as Inferred Resources, contain 1,020,000 ounces.

The resource estimate considers that mineralization starts at surface and continues to a depth of approximately 900 metres. This updated resource estimate does not include results of ongoing definition and exploration drilling performed in 2010 and 2011. The deposit remains open in all directions.

Mineral Resources above an average 220-metre depth from surface are considered to be amenable to open pit extraction, whereas mineral resources below this depth are considered to be amenable to underground extraction.

Potential open pit mineral resources are reported at a cut-off of 0.5 grams per tonne gold, whereas potential underground mineral resources are reported at a cut off of 2.5 grams per tonne gold. The consolidated mineral resource statement for Eau Claire is tabulated in Table 1. Table 2 demonstrates that there is in excess of one million total ounces of gold contained in the Measured and Indicated resource category at all cut-off grade sensitivities. At a 4.0 g/t cut-off the Inferred mineral resource of 420,000 tonnes contains 262,000 ounces of gold at 19.37 g/t capped or 277,000 ounces of gold at 20.47 g/t uncapped.

Highlights of the Eau Claire mineral resource estimate include:

• Measured and Indicated Open Pit resources at an average grade of 5.15 grams per tonne gold (5.72 grams per tonne gold uncapped) containing 452,000 ounces gold (502,000 ounces gold uncapped);

• Inferred Open Pit resources at an average grade of 2.56 grams per tonne gold (2.83 grams per tonne gold uncapped) containing 115,000 ounces gold (127,000 ounces gold uncapped);

• Measured and Indicated Underground resources at an average grade of 6.46 grams per tonne gold (capped and uncapped) containing 130,000 ounces gold (capped and uncapped);

• Inferred Underground resources at an average grade of 7.18 grams per tonne gold (7.21 grams per tonne uncapped) containing 905,000 ounces gold (910,000 ounces gold uncapped).

Eastmain President and CEO, Dr. Donald J. Robinson stated "This updated mineral resource estimate demonstrates that the Eau Claire gold deposit has excellent potential for both open pit and underground mineral resources at significant grade. Detailed delineation drilling and surface sampling has improved our understanding of the mineralization at Eau Claire, while establishing a Measured and Indicated resource of 0.58 million ounces (0.63 million ounces uncapped) and an Inferred resource of 1.02 million ounces (1.04 million ounces uncapped). We believe the likelihood of adding additional resource ounces in the future is high."

This updated resource estimate does not include subset veins lying within the estimated pit area, nor does it include substantial infill sampling completed between veins sets or drilling completed in 2010. Thus, there is excellent potential to expand both the open pit and underground gold resources at Eau Claire. An aggressive 25,000-metre definition and exploration drill program, together with continued infill sampling to expand potentially open-pit material between high-grade veins at Eau Claire, will be the focus in 2011. 

"We will persist with our strategy to advance the deposit towards a production and development scenario". Robinson adds, "Eastmain's recent acquisition of 100% of the outstanding royalty associated with the project also demonstrates our commitment to unlocking the potential of Eau Claire to the future benefit of our shareholders. As resources increase, a future Clearwater royalty becomes increasingly more valuable".

The Eau Claire gold deposit consists of a stacked set of quartz-tourmaline +/- carbonate sheeted veins (VQTL) aligned in a three-dimensional, en-echelon pattern from northwest to southeast within a structural corridor. Gold-bearing veins extend over an area of at least 1,500 metres in length to a depth of over 900 metres. Gold also occurs within altered rock composed of actinolite and tourmaline, with accessory biotite and calcite, which generally forms a 10-cm to multi-metre envelope on vein margins.

More than 30 parallel, gold-bearing quartz-tourmaline veins and alteration zones, generally ranging from one to four metres and locally up to 9.0 metres in width, have been intersected in the Eau Claire Deposit. These veins range from 75 to 300 metres in length and have been traced by Diamond drilling to a vertical depth of approximately 900 metres. 

The main set of gold-bearing veins is oriented N85°E and dips 45° to 60° south. Drilling indicates there is a pronounced plunge to the mineralized zone, defined by these veins, in a direction of approximately 45° southeast. However, there also appears to be at least one secondary orientation or rake to the southwest that has not been fully delineated. 

A series of crosscutting north-south auriferous veins defined on surface have also been intersected in drilling, though their relationship to the deposit has not yet been fully defined.

There is potential to increase both the Open Pit and Underground resources both within the Eau Claire deposit and the adjacent 850 West Zone. The mineral resource estimate does not include 2010 drilling completed on the 850 West Zone, nor does it include channel sample data from high grade veins V12 and V16 found in this area. An infill sampling program was initiated in 2010 to assay unsplit core located between the high grade veins, which locally has been determined to be gold-bearing. This data has not been included in the estimate.

Both Eau Claire and the 850 West Zone are open at depth. A 25,000-metre drill program has been initiated to continue definition drilling and expansion drilling within and lateral to presently defined resources.

The updated resource calculations were prepared by Eugene Puritch, P. Eng., Antoine Yassa, P.Geo. and Tracy Armstrong, P.Geo. of P & E Mining Consultants Inc. ("P&E") of Brampton, Ontario, Qualified Persons under NI 43-101 who are independent of the Company.

Eugene Puritch, P. Eng., President of P&E, and Dr. Donald J. Robinson P. Geo, President and Chief Executive Officer of Eastmain, both Qualified Persons under National Instrument 43-101 have reviewed and approved the updated resources and the technical data presented in this press release.

Eastmain has not completed a feasibility study in regards to the mineral resources presented herein and there is no certainty that proposed operations will be economically viable. An NI 43-101 compliant report to support the above mineral resource will be available on SEDAR within 45 days of the date of this press release.

Eastmain has begun a $5-million exploration program at its wholly-owned Clearwater Project. Work includes approximately 25,000 metres of definition and exploration drilling in and around the Eau Claire deposit, which begins today. In addition surface mapping, prospecting and trenching of new targets elsewhere on the property will begin in June.

About Eastmain Resources Inc. (News - Market indicators)

Eastmain is a Canadian gold exploration company with 100% interest in the Eau Claire and Eastmain gold deposits. The Corporation has $22.5 Million in working capital and holds a pipeline of exploration projects within the James Bay District, including the Éléonore South property. Eastmain has allocated $9.3 million for exploration of its key gold projects in Québec. Work will include 46,000 metres of drilling in 2011.

Forward Looking Statements – Certain information set forth in this news release may contain forward-looking statements that involve substantial known and unknown risks and uncertainties. These forward-looking statements are subject to numerous risks and uncertainties, certain of which are beyond the control of Eastmain, including, but not limited to the impact of general economic conditions, industry conditions, dependence upon regulatory approvals and the availability of financing. Readers are cautioned that the assumptions used in the preparation of such information, although considered reasonable at the time of preparation, may prove to be imprecise and, as such, undue reliance should not be placed on forward-looking statements.