Great Panther
Great Panther


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Introduction
Location Map - click to view enlarged
Location Map

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 traveling 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 6,438 hectares. The concessions are 100%-owned by Great Panther's Mexican subsidiary, Minera Mexicana El Rosario, SA de CV (MMR).
click to view enlarged
Topia Concessions
In February of 2005, MMR exercised its option to earn a 100% interest in the bulk of the concessions. There is no underlying Net Smelter Royalty on the property.


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
The 2009 mineral resource estimate, delivered by Wardrop in June, comprises Measured & Indicated Mineral Resources of 173,103 tonnes at 552g/t silver, 0.99g/t gold, 5.58% lead and 4.83% zinc (5,458,218 silver equivalent ounces) as well as 174,562 tonnes of 633g/t silver, 1.03g/t gold, 5.10% lead and 3.84% zinc (5,692,957 silver equivalent ounces) in the Inferred category. At current production levels, management considers the new resource to be sufficient for at least a 10 year mine life.

The 2009 mineral resource estimate provides an update for the Argentina vein only, while the estimate delivered by Wardrop in 2006 for some of the other veins on the property came largely from the verification of resources defined by Peñoles.These resources are still intact as mining to date by Great Panther has come from new mine development. The new total contained metal for each resource category is shown in Table 1 below.

Table 1. Contained Metal (all veins):

Category

Tonnes

Ag ozs

Au ozs

Pb lbs

Zn lbs

Ag oz Eq

M & I Resources

173,103

3,080,954

5,507

21,278,080

18,430,862

5,458,218

Inferred Resources

174,562

3,560,237

5,793

19,585,856

14,746,998

5,692,957


At the current production rate of approximately 30,000 tonnes per year, and considering that not all resources may be mined, management expects the resources above to support a mine life at Topia of at least 10 more years. The Company plans to continue the systematic replacement of annual production with new resources. This "rolling resource" is typical for underground mines as it is often not cost-effective to define a large resource/reserve in advance of mining.

Production
Great Panther refurbished the mill during the second half of 2005, and recommissioned the mill in December 2005. Throughout 2009, the mill has operated at approximately 100 tonnes per day.

Metal production for the third quarter of 2009 totaled 110,724 oz Ag, 79 oz of Au, 464,510 lbs of Pb, and 580,043 lbs of Zn, (for a total of 164,262 Ag eq oz), from milling 7,680 tonnes of ore. The silver production represents a 5% increase from Q3 2008. The ore grades, at 492g/t Ag, 0.4g/t Au, 2.95% Pb and 3.84% Zn, (or 23.62 Ag eq oz), represent a 10% improvement over Q3 2008.

Topia plant performance continues to excel with metal recoveries of 91.2% for Ag (a record), 79.8% for Au, 93.0% for Pb (a record) and 89.3% for Zn (a record). Concentrate qualities were at record highs, with the lead concentrate at 57.2% Pb and 8,971 g/t Ag, and the zinc concentrate at 54.8% Zn.

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.

Plans and Sections of the Topia Mines
Vein Traces, Drilling and Active Work Areas - click to view enlarged
Vein Traces, Drilling and Active Work Areas
at the Topia Mine
Topia San Miguel & Hormiguera Plan Map - click to view enlarged
Hormiguera Extension of the
Cantarranas Vein
Section through San Miguel Mine - click to view enlarged
Section through San Miguel Mine
Section through Hormiguera Mine - click to view enlarged
Section through Hormiguera Mine
Section through Recompensa and El Rincon Mines - click to view enlarged
Section through Recompensa and El Rincon Mines
Plan of Recompensa and El Rincon Mines - click to view enlarged
Plan of Recompensa and El Rincon Mines
Plan View of La Dura and Don Benito Veins - click to view enlarged
Plan View of the La Dura and Don Benito Veins
Underground Exploration on the Don Benito South Vein - click to view enlarged
Underground Exploration on the Don Benito South Vein
Underground Exploration on the Don Benito North Vein - click to view enlarged
Underground Exploration on the Don Benito North Vein
Topia San Gregorio and El Rosario Mines in Plan View
San Gregorio and El Rosario Mines
San Gregorio Section - click to view enlarged
San Gregorio Section View
Topia El Rosario Section View - click to enlarge
Topia El Rosario Section View
Plan View of Argentina Vein and Workings - click to view enlarged
Underground Exploration on the
Argentina Vein
Argentina Longsection-click to view
Section view of the
Argentina Vein


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 approximately 90 of these drill holes were used in preparing the August 2009 43-101 report by Wardrop Engineering. The company has subsequently drilled a further 60 underground and surface holes, the most recent drilling focusing on the Hormiguera area in the northeast of the property, and the Recompensa area in the southwest.


Management
Management of the Topia Mine Project is by Ing. Javier Ramirez Vargas, General Manager of the Topia Mine. Robert Brown is the Qualified Person responsible for all technical information obtained and reported on.
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Presentations Topia Crushing Plant (Windows Media, 5.9 Mb) Topia Mill & Flotation Circuits (Windows Media, 2.7 Mb)

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Tue Aug 25, 2009
NI 43-101 Resource Estimate for the Argentina Veins - Topia Mine - August 2009

(655 KB)

Thu Feb 1, 2007
NI 43-101 Technical Report for Topia Mine

(3905 KB)

Summary Report on the Topia Project - November 2003
(3265 KB)

Project Evaluation of the Topia Mines - January 2005
(867 KB)


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