MAG Silver Corp.
TSX VENTURE : MAG
AMEX : MVG

MAG Silver Corp.

September 13, 2007 04:00 ET

MAG Silver & Penoles Report High Grade Silver and Gold at Valdecanas

6.45 metres (5.85 metres true width) grading 1,634 g/t silver (47.7 opt), 0.52 g/t gold and 7.77% lead/zinc

VANCOUVER, BRITISH COLUMBIA--(Marketwire - Sept. 13, 2007) - MAG Silver Corp. (TSX VENTURE:MAG)(AMEX:MVG) ("MAG") and Industrias Penoles S.A.B. de C.V. ("Penoles") announce results from Hole GC and provide an update on the results from Hole GD. Hole GC has returned a core length of 6.45 metres (5.85 metres true width) grading 1,634 grams per tonne (g/t) silver (47.7 ounces per ton (opt)), 0.52 g/t gold, 3.02% lead and 4.75% zinc. Hole GC has intersected the Valdecanas Vein 110 metres up-dip from Hole GD which was reported in a press release dated July 10, 2007 (see table below for details).

With regards to Hole GD there were two analytical results within the previously reported assay record that were classified as over-limits. From 809.8 to 810.55 metres (0.75 metres) the silver reported was in excess of 10,000 g/t and the re-assay value is 15,026 g/t silver. In the second over-limit from 814.45 to 815.55 metres (1.10 metres) the value for lead was in excess of 30.0% and re-assay value is unchanged at 30% lead. The final overall results for Hole GD are as follows: from 803.4 to 824.65 a core length of 21.25 metres (16.28 metres true width) returned 1,343 g/t silver (previously 1,175 g/t silver), 3.76 g/t gold, 7.73% lead and 5.73% zinc.

The final assay results for Hole GD also identified a second, hanging wall vein almost 11.0 metres above the Valdecanas Vein. This intersection returned 1.50 metres (1.30 metres true width) of 421 g/t silver (12.3 opt), 1.11 g/t gold, 1.10% lead and 1.62% zinc.

Drilling confirms high grade mineralization in the Valdecanas Vein in Holes GD and GC as well as the presence of a post-mineral fault between Sections I and G. The fault appears to move the vein closer to the northern property boundary but more drilling is required to determine the vein's orientation farther west and north. The vein remains open to the west and down dip and has been defined to near the east property limit (to view longitudinal section and Drill Plan please click on the following link: http://www.ccnmatthews.com/docs/MAG0913.pdf, or visit www.magsilver.com).



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True
Width Silver Silver Gold Lead Zinc Width
Hole # From To metres g/t opt g/t % % metres
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JI-06-GC 731.75 738.20 6.45 1,634 47.7 0.52 3.02 4.75 5.85
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JI-06-GD
Hanging Wall 791.30 792.80 1.50 421 12.3 1.11 1.10 1.62 1.30
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JI-06-GD
Valdecanas 803.40 824.65 21.25 1,343 39.2 3.76 7.73 5.73 16.28
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There are presently three holes in progress; Holes GB (at 525 metres depth), IC (at 389 metres depth) and OF (at 681 metres depth). Almost 9.0 kilometres of new drill roads have been constructed in the last month, mostly to the west of Valdecanas in anticipation of further drilling on section "E".

These drill results are from the 28,000 metre definition drill program currently underway on the Valdecanas silver/gold vein discovery within the Juanicipio Joint Venture, Fresnillo District, Zacatecas State, Mexico.

About the Joint Venture

Penoles has earned a 56% interest in the Juanicipio property. MAG retains a 44% interest in the property. Penoles and MAG will now participate in the project as a joint venture and will share expenditures on a pro rata basis, with Penoles contributing 56% and MAG 44% respectively. Penoles maintains its position as operator of the project and will present programs to the joint venture management team for joint approval going forward.

The Penoles/MAG Juanicipio Joint Venture lies 5 kilometres west from the principal production head-frame of the Fresnillo Mine and 1.5 kilometres west from the Saucito Vein, currently undergoing preproduction development with construction of a 600 metre shaft and a 2,200 metre decline.

Quality Assurance and Control: The samples are shipped directly in security sealed bags to ALS-Chemex Laboratories preparation facility in Guadalajara, Jalisco, Mexico (Certification ISO 9001). Samples shipped also include intermittent standards and blanks. Pulp samples are subsequently shipped to ALS-Chemex Laboratories in North Vancouver, Canada for analysis. Two extra pulp samples are also prepared and are analyzed (in progress) by SGS Laboratories (Certification ISO 9001) and Inspectorate Laboratories (Certification ISO 9001) (or other recognized lab). The bulk reject is subsequently sent to CIDT (Center for Investigation and Technical Development) of Penoles in Torreon, Mexico for metallurgical testing where a fourth assay for each sample is analyzed and a calculated head grade is received on the basis of a concentrate balance. The CIDT also does a full microscopic, XRF and XRD mineralogical analysis.

Qualified Person: Dr. Peter Megaw, Ph.D., C.P.G., has acted as the qualified person as defined in National Instrument 43-101 for this disclosure and supervised the preparation of the technical information in this release. Dr. Megaw has a Ph.D. in geology and more than 20 years of relevant experience focussed on silver and gold mineralization, and exploration and drilling in Mexico. He is a certified Professional Geologist (CPG 10227) by the American Institute of Professional Geologists and an Arizona registered geologist (ARG 21613). Dr. Megaw is not independent as he is a Director and Shareholder of MAG and is a vendor of one project, other than Juanicipio, whereby he may receive additional shares. Dr. Megaw is satisfied that the results are verified based on an inspection of the core, a review of the sampling procedures, the credentials of the professionals completing the work and the visual nature of the silver and base metal sulphides within in a district where he is familiar with the style and continuity of mineralization.

About Penoles (www.penoles.com.mx)

Industrias Penoles, S.A.B. de C.V. and its subsidiaries make up one of Mexico's largest industrial conglomerates. Since its founding in 1887, this group has been engaged in the sustainable exploitation of non-renewable natural resources. Penoles is an integral part of Grupo BAL, a private, diversified group made up of independent Mexican companies ranging from mining to insurance to retail. Penoles' productive operations are currently located in Mexico, where it operates the world's richest silver mine (Fresnillo), the world's fourth largest metallurgical complex in terms of the value of its production, and the largest sodium sulphate plant in the world. These operations make Penoles the world's largest producer of refined silver, metallic bismuth and sodium sulphate, and a leader in Latin America in refined gold, lead and zinc.

About MAG Silver Corp. (www.magsilver.com)

MAG is focused on district scale projects located within the Mexican Silver Belt. Our mission is to become one of the premier companies in the Silver Mining Industry. MAG and its partner Penoles are delineating a significant new silver vein discovery on the Juanicipio Joint Venture in Zacatecas State, Mexico. MAG is based in Vancouver, British Columbia, Canada. Its common shares trade on the TSX-V under the symbol MAG and on AMEX under the symbol MVG.

On behalf of the Board of MAG SILVER CORP.

Dan MacInnis, President and CEO

This release includes certain statements that may be deemed to be "forward-looking statements" within the meaning of the US Private Securities Litigation Reform Act of 1995. All statements in this release, other than statements of historical facts that address future mineral production, reserve potential, exploration drilling, exploitation activities and events or developments that MAG expects, are forward-looking statements. Forward-looking statements are often, but not always, identified by the use of words such as "seek", "anticipate", "plan", "continue", "estimate", "expect", "may", "will", "project", "predict", "potential", "targeting", "intend", "could", "might", "should", "believe" and similar expressions. These statements involve known and unknown risks, uncertainties and other factors that may cause actual results or events to differ materially from those anticipated in such forward-looking statements. Although MAG believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results or developments may differ materially from those in the forward-looking statements. Factors that could cause actual results to differ materially from those in forward-looking statements include changes in commodities prices, changes in mineral production performance, exploitation and exploration successes, continued availability of capital and financing, and general economic, market or business conditions.

Please Note: Investors are urged to consider closely the disclosures in MAG's annual and quarterly reports and other public filings, accessible through the Internet at www.sedar.com and www.sec.gov/edgar/searchedgar/companysearch.html.

Neither the TSX Venture Exchange nor the American Stock Exchange has reviewed or accepted responsibility for the accuracy or adequacy of this news release, which has been prepared by management.

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