Sierra Ramirez

SIERRA RAMIREZ PROPERTY
MUNICIPIO SAN JUAN de GUADALUPE DURANGO, MEXICO

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September 2008

Sierra Ramirez another district-scale CRD project; MAG owns 100% of historic high-grade silver-lead-zinc producer

The Sierra Ramirez District lies in eastern Durango State, approximately 80 kilometres west of the famous Providencia-Concepcion del Oro, Zacatecas District. Sierra Ramirez is a typical Mexican CRD target with a long production history of silver, lead and zinc.

Originally, MAG acquired an option from Minera Rio Tinto of Chihuahua, Mexico to earn 100% interest in over 80% of the district. In 2007 MAG negotiated acquisition of the remaining 20% that covers the main area of extensive mine workings. We now control 100% of a large landholding (200 square kilometres) covering a Carbonate Replacement Deposit District that produced high-grade silver-lead-zinc ores (silver grades in the 1,000-3,000 g/t range) from Spanish colonial times to the mid-1960s.


MAG first to consolidate the district and conduct modern exploration

The old mines of Sierra Ramirez were never operated below the oxide zone (200 metres) as evidenced by the lack of sulphide found in the mine dumps. Mineralization is widespread along 20 kilometres of the "Sierra Ramirez Range". This the first time the district has been consolidated and modern exploration techniques employed.


Property characteristics and initial work

The Sierra Ramirez property is a 7 by 15 kilometre E-W oriented anticline fold composed of Jurassic Zuloaga Limestone cut by at least 2 rhyolite plugs. Mineralization consists of silver-lead-zinc replacement veins in the western part of the area and mantos hosted in distinct carbonate strata in the central and eastern portions. Small amounts of skarn are known to exist proximal to the rhyolite areas. Exploration of the district will involve the unraveling of the overall controls and metal zoning to best define the most favorable areas for further exploration.

Initially MAG Silver executed district-scale mapping and sampling in 2004, with a focus on determining the size of the mineralized zone(s) and confirming existing concepts of district metal zoning. The resulting district-scale metal ratio zoning patterns revealed three principal mineralization centres.

Unfortunately inclement weather and other priorities resulted in little field work in 2006.


Program results: 2007

MAG Silver flew a 2,000 line kilometre magnetic and electromagnetic survey, completed in February 2007, that enhanced our knowledge and provided direct targeting in a number of favourable areas.

Results of the work point to the "San Acacio" area, marked by the multiple parallel structures, as the obvious first place to drill test. The old mine workings are extensive and give us evidence of where the high-grade pods blossomed out along the structures. It is proposed to examine the structural fabric in some detail to determine if there are inflections or intersections that determine where the pods are.


Outlook

Sierra Ramirez is our least developed CRD property but a very large prospect with exploration potential.