Trevali Drills Thickest Mineralized Intercept to Date at Halfmile Lead-Zinc-Copper-Silver Deposit in New Brunswick, Canada

Vancouver, British Columbia, CANADA

VANCOUVER, BRITISH COLUMBIA--(Marketwire - April 28, 2011) -

29.25 metres of 6.87% zinc, 2.23% lead, 0.46% copper, 52 g/t silver and 0.86 g/t gold

Copper-rich feeder zone identified, including 7 metres at 2.63% copper

Silver grades increased by 250%

Trevali Mining Corporation ("Trevali" or the "Company") (TSX:TV)(OTCQX:TREVF) is pleased to announce initial drill results from its metallurgical test program of the Upper Zone at its Halfmile Lead-Zinc-Copper-Silver Deposit in New Brunswick, Canada. Drilling has intersected substantially thicker zones of massive sulphide in the deposit, in addition to new zones of high-grade copper in the Hanging Wall. Mineralization remains open for expansion. Silver and gold grades are elevated in the lead-zinc dominant portion of the massive sulphide body.


  • Drill results (Table 1) confirm higher silver content, averaging 59.9 g/t silver (weighted average 55.5 g/t) versus 16.95 g/t silver for the Upper Zone as noted in the NI43-101 resource estimation - an increase of approximately 250%. The majority of the historic drilling campaigns did not routinely assay for silver.
  • Gold values for Upper Zone averages 0.55 g/t (weighted average of 0.6 g/t). Gold was not included in the NI43-101 resource estimate.
  • Massive sulphide intercepts in the central part of Upper Zone are thickening to depth – varying from 9 to 29 metres, averaging approximately 18 metres.
  • A new copper-rich stringer zone over 3.63-to-7.0 metre drill-indicated widths with intercepts ranging from 0.86% to 2.97% copper has been identified.
  • Continuity of grade and width within the massive sulphide Upper Zone is confirmed.


The recently completed 2,500-metre metallurgical and geotechnical drill program was undertaken to quantify the precious metal content of the Halfmile Upper Zone portion of the deposit that is being targeted in the initial phase of underground mine development expected to commence imminently.

The assay results of all recent drilling are summarized in the table below and locations are illustrated in the Longitudinal Projection (Figure 2).

A February 2009 NI43-101 compliant mineral resource estimate on Halfmile reviewed an Indicated Resource of 6.26 million tonnes at 8.13% zinc, 2.58% lead, 0.22% copper and 30.78 g/t silver plus an additional Inferred Resource of 6.08 million tonnes at 6.69% zinc, 1.83% lead, 0.14% copper and 20.51 g/t silver all using a 5.0% capped zinc equivalent cut-off grade.

To view the first map associated with this release, please click here:

DHIDZoneLength%Zn%Pb%Cug/t Agg/t Au
HW Cu3.630.120.042.7115.630.37
HW Cu6.
HW Cu2.
HW Cu6.
HW Cu1.
Main MS23.326.431.920.3442.800.47
HK11-09Main MS6.692.610.630.54112.280.81
HW Cu8.
HW Cu7.

To view the first map associated with this release, please click here:

Qualified Person and Quality Control/Quality Assurance

EurGeol Dr. Mark D. Cruise, Trevali's President and CEO and a qualified person as defined by National Instrument 43-101, has supervised the preparation of the scientific and technical information that forms the basis for this news release. Dr. Cruise is not independent of the Company, as he is an officer and shareholder.

The work programs at Halfmile were supervised, reviewed and approved by Dayle Rusk, P. Geo., Vice President Exploration of Kria, a Qualified Person as defined under NI 43-101 guidelines, and who was responsible for all aspects of the work, including the quality control/quality assurance programs. On-site personnel at the project rigorously collect and track samples which are then security sealed and shipped to Activation Laboratory Ltd's sample preparation facility in Fredericton, New Brunswick with subsequent assaying using multi-acid digest ICP-AES and ASS techniques at their laboratory in Ancaster, Ontario, Canada. Activation's quality system complies with the requirements for the International Standards ISO/IEC 17025 with CAN-P-1579 designation. Analytical accuracy and precision are monitored by the analysis of reagent blanks, reference material and replicate samples. Quality control is further assured by the use of international and in-house standards.

Trevali is advancing two polymetallic deposits to production in Canada and Peru – the Halfmile and Santander projects respectively. In Canada, through its recent acquisition of Kria Resources, Trevali acquired the Halfmile and Stratmat polymetallic deposits near Bathurst, New Brunswick, and the Ruttan copper-zinc deposit in northern Manitoba (Figure 1). Advanced permitting and engineering studies are in progress at Halfmile with proposed production at a rate of 2,000-tonnes-per-day anticipated to commence in 2011.

At Santander, in conjunction with Glencore International A.G., mine commissioning and production is anticipated to commence at 2,000-tonne-per-day in late 2011 with full production to follow immediately thereafter. Additionally, through its subsidiary, Trevali Renewable Energy Inc., Trevali is undertaking a significant upgrade of its wholly-owned Tingo run-of-river hydroelectric generating facility along with transmission line upgrades and extensions to allow, in addition to supplying power to the mining operation on the property, the potential sale of surplus power into the Peruvian National Energy Grid.

Please refer to the Kria's technical reports filed on SEDAR for details regarding the NI 43-101 compliant resource estimates on Halfmile, Stratmat and Ruttan. Additional information is available at

The common shares of Trevali are currently listed on the TSX (symbol TV). For further details on Trevali, readers are referred to the Trevali's web site ( and to Canadian regulatory filings on SEDAR at

On Behalf of the Board of Directors of Trevali Mining Corporation

Mark D. Cruise, President

This news release contains "forward-looking statements" within the meaning of the United States private securities litigation reform act of 1995 and "forward-looking information" within the meaning of applicable Canadian securities legislation. Statements containing forward- looking information express, as at the date of this news release, the Company's plans, estimates, forecasts, projections, expectations, or beliefs as to future events or results and the company does not intend, and does not assume any obligation to, update such statements containing the forward-looking information. Such forward-looking statements and information include, but are not limited to statements as to: the accuracy of estimated mineral reserves and resources, anticipated results of future exploration, and forecast future metal prices, anticipated results of future electrical sales and expectations that environmental, permitting, legal, title, taxation, socio-economic, political, marketing or other issues will not materially affect estimates of mineral reserves. These statements reflect the Company's current views with respect to future events and are necessarily based upon a number of assumptions and estimates that, while considered reasonable by the Company, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies.

These statements reflect the Company's current views with respect to future events and are necessarily based upon a number of assumptions and estimates that, while considered reasonable by the company, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements contained in this news release and the company has made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: fluctuations in spot and forward markets for silver, zinc, base metals and certain other commodities (such as natural gas, fuel oil and electricity); fluctuations in currency markets (such as the Peruvian sol versus the U.S. dollar); risks related to the technological and operational nature of the Company's business; changes in national and local government, legislation, taxation, controls or regulations and political or economic developments in Canada, the United States, Peru or other countries where the Company may carry on business in the future; risks and hazards associated with the business of mineral exploration, development and mining (including environmental hazards, industrial accidents, unusual or unexpected geological or structural formations, pressures, cave-ins and flooding); risks relating to the credit worthiness or financial condition of suppliers, refiners and other parties with whom the Company does business; inadequate insurance, or inability to obtain insurance, to cover these risks and hazards; employee relations; relationships with and claims by local communities and indigenous populations; availability and increasing costs associated with mining inputs and labour; the speculative nature of mineral exploration and development, including the risks of obtaining necessary licenses and permits and the presence of laws and regulations that may impose restrictions on mining,; diminishing quantities or grades of mineral reserves as properties are mined; global financial conditions; business opportunities that may be presented to, or pursued by, the Company; the Company's ability to complete and successfully integrate acquisitions and to mitigate other business combination risks; challenges to, or difficulty in maintaining, the Company's title to properties and continued ownership thereof; the actual results of current exploration activities, conclusions of economic evaluations, and changes in project parameters to deal with unanticipated economic or other factors; increased competition in the mining industry for properties, equipment, qualified personnel, and their costs. Investors are cautioned against attributing undue certainty or reliance on forward-looking statements.

Although the Company has attempted to identify important factors that could cause actual results to differ materially, there may be other factors that cause results not to be as anticipated, estimated, described or intended. The Company does not intend, and does not assume any obligation, to update these forward-looking statements or information to reflect changes in assumptions or changes in circumstances or any other events affecting such statements or information, other than as required by applicable law.

The TSX has not approved or disapproved of the contents of this news release.

Contact Information:

Trevali Mining Corporation
Steve Stakiw
Manager - Corporate Communications
(604) 488-1661
(604) 408-7499