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Introduction
The Topia Silver-Lead-Zinc property is located in the heart of the Topia Mining District in west-central Durango State, Mexico. The property is accessible by road from the city of Durango by travelling north for approximately 200 km on paved Highway 23, and west for 150 km on a paved and gravel road to the town of Topia. The town is presently served by daily small-aircraft flights to the city of Culiacán, which lies 100 km to the southwest. Topia is the principal centre for the area with schools, shops, a small hospital, and public telephone and internet access. The property consists of four discrete blocks of mineral exploitation concessions covering 6,344 hectares. The concessions are 100%-owned by Great Panther's Mexican subsidiary, Minera Mexicana El Rosario, SA de CV (MMR).
Historical Production The Topia Mining District is one of the oldest in Mexico, the discovery of silver dating back to 1538. Artisanal mining continued for centuries until the Topia Silver Mine was opened in 1952 by Minera Mexicana Peñoles, now Mexico's largest silver producer. Peñoles built a 200 tonne per day mill on site and operated the mine continuously until 1989. A private company continued production on a small scale until 1999. Total historical production for the district has been estimated at 30 million ounces of silver. The recorded production for 1952-1999 exceeds 15 million ounces of silver, as well as 18,500 ounces of gold, 48,000 tonnes of lead and 44,500 tonnes of zinc. The on-site mill complex treated the ore and produced lead and zinc concentrates that were shipped to the Peñoles smelter in Torreon. Records for Peñoles' 38 years of production indicate average mill head grades of 437 g/t silver, 0.87 g/t gold, 3.9% lead and 4.2% zinc. Overall average metal recoveries were silver-86%, gold-55%, lead-94% and zinc-85%. Resource Estimate Wardrop Engineering submitted an update to their 43-101 compliant report on Topia in August 2008. They estimated: > Measured and Indicated Mineral Resource of 153,373 tonnes grading 501g/t silver, 0.95g/t gold, 5.38% lead, and 4.85% zinc. > Inferred Mineral Resource of 98,083 tonnes grading 468g/t silver, 0.97g/t gold, 3.59% lead, and 2.95% zinc. The estimated total metal content of this resource is 3.95M oz silver, 7,718 oz gold, 25.96M lb lead, and 22.77M lb zinc. Production Great Panther refurbished the mill during the second half of 2005, and recommissioned the mill in December 2005. The mill is operating at approximately 100 tonnes per day, (August 2008). Silver equivalent production in the second quarter of 2008 was 160,557 oz while head grades increased from the previous quarter. Head grades in Q2 2008 averaged 360 g/t silver, 0.85 g/t gold, 2.82% lead and 2.93% zinc. In this period a total of 8,649 tonnes of material was processed from the Topia Mine, with recoveries between 81% and 92%. The Company is continuing to rehabilitate the historic workings on the property with special focus on the 1522 Mine and and Argentina Mine. In addition to the stopes currently being developed on the Madre and Dos Amigos Veins in the 1522 Mine, a third vein - Cantarranas - is being evaluated for its production potential. The Veta Madre and Veta Cantarranas are both several kilometers long and provided the bulk of the ore for past mining production. Mineralization Mineralization within the Topia Mine is that of a typical silver-lead-zinc epithermal vein system, formed along a series of northeast trending faults within the Tertiary-aged Lower Series Volcanics. The mined vein horizon consists of quartz, galena, sphalerite and pyrite and lesser amounts of arsenopyrite, marcasite, chalcopyrite, silver-rich sulphosalts, electrum, muscovite and carbonates. At Topia, the historically mined ore-grade or "productive" veins are confined to a limited vertical extent of 200 to 300 metres, but can extend laterally along strike for as much as 4 kilometres. This productive vein horizon grades downward into barren coarse-grained quartz, and upwards into barren, cherty, quartz-calcite-barite. Historically, the three most prolific veins on the property were the Veta Madre, Argentina and Cantarranas. The Topia District contains multiple veins, most of which lie on the Great Panther property. Recent Exploration Prior to exercising the option agreement, Great Panther conducted a 30-hole (7,437-metre) diamond drilling program that tested five separate areas on the property. Three of these areas; Las Trancas, Don Benito and Hormiguera; represent portions of the same vein that extends for more than four kilometres across the property. The two other areas represent parallel vein systems approximately one kilometre to the northwest (Argentina) and two kilometres to the southeast (El Rosario). Several other veins are known on the property and have yet to be drilled. Since 2005, MMR staff has been continually re-assessing the Topia mine, and resampling the veins to confirm that the resource blocks outlined by Penoles are viable targets. A comprehensive surface and underground drill program, begun in July 2006 has targeted potential resource blocks and explored several veins which have had little or no previous exploitation. Data from many of these 90 drill holes (up to June 2008) were used in preparing the most recent 43-101 report by Wardrop Engineering. Management Management of the Topia Mine Project is by Great Panther's Vice-President of Exploration, Robert Brown, P.Eng, and Vice-President of Operations, Ing. Francisco Ramos. Robert Brown is the Qualified Person responsible for all technical information obtained and reported on. Presentations Topia Crushing Plant (Windows Media, 5.9 Mb) Topia Mill & Flotation Circuits (Windows Media, 2.7 Mb)
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