Nov 9 2010
Hana Mining Ltd. (TSX VENTURE:HMG)(FRANKFURT:4LH) has announced final results on the first locked cycle tests on sulphide material from the Banana Zone at the Ghanzi Project.
The results show that the copper-silver mineralization at the Banana Zone sulfide mineralization is highly amenable to conventional flotation recovery technology.
Highlights of recent metallurgical results:
- Initial locked cycled tests, at a coarse grind size of 150 microns, show a copper recovery of 92.75% and a silver recovery of 80.58%.
- The tests also show a final concentrate grade of 43.55% copper, 853.57 g/t silver and 0.73% molybdenum.
- Molybdenum recoveries in the copper concentrate were highly encouraging with an average recovery of 78.28%.
- Metallurgical work on applying conventional flotation technology on oxide and transitional material from the Banana Zone and sulphide material from the Chalcocite Zone is ongoing.
- Given the encouraging recoveries and concentrate grades of the molybdenum, Hana will look at the feasibility of producing a saleable molybdenum concentrate.
Discussion of Results:
The preliminary metallurgical testing program was designed to determine the grinding and flotation characteristics of a Banana Zone-sulphide mineralization sample which is indicative of the current Ghanzi NI 43-101 compliant resource estimate. The test data will be used to develop a process flow sheet, to identify further testing requirements, and to develop capital and operating costs for the Preliminary Economic Assessment which is scheduled to be completed by the end of 2010.
Mineralized material submitted for testing came from composite material from New Discovery, Northeast Fold and South Limb areas. Therefore, the above results are indicative of the mineralized sulphide material at the Banana Zone.
In the Banana Zone, sulphide composite bornite and chalcocite represent 95% of the copper mineralization. Approximately 80% of the copper minerals are liberated at a coarse grind size of 150 microns, while copper minerals which are not liberated are associated with hard silicates and phyllosilicates.
Initial locked cycled metallurgical tests on the sulphides from the Banana Zone show that the mineralized material is highly amenable to conventional flotation methods resulting in a copper recovery of 92.75%, and a silver recovery of 80.58%. The testing also showed that conventional flotation can produce a relatively high grade concentrate, with average grades of 43.55% copper and 853.57 g/t silver. For comparison, most conventional copper sulphide mining and milling operations produce a product with concentrate grades of 25% to 30% copper. Therefore, the Banana Zone will produce a very high quality product that should elicit considerable interest from global copper smelters.
Highly encouraging results were also received on the contained molybdenum which showed a molybdenum recovery of 78.28% with the bulk concentrate grade of 0.73% molybdenum. Given the encouraging molybdenum results, Hana will move forward with additional work to evaluate the viability of producing a separate molybdenum concentrate. Results are not expected to be available until sometime in 2011.
Development Update:
The following engineering and consultation activities are ongoing to fulfill the goal of completion of a PEA by Q4 2010:
- Preliminary mine open pit modeling has been carried out using the April 2010 resource as a basis to define the parameters to be used. A revised model will be completed after the 2010 drilling has been incorporated;
- Resource modeling is progressing as expected and a NI 43-101 compliant resource estimate for the Banana and Chalcocite Zones is expected to be released soon;
- Metallurgical (column leaching) work, which is being carried out by Metcon Research in Tuscon, Arizona, on Banana Zone Oxide and on Chalcocite Zone composites is ongoing. Results are expected to be available by the end of the year;
- Field work for water exploration is ongoing.
Qualified Person and Quality Assurance/Quality Control
Metallurgical test work was carried out by MINTEK of Johannesburg, South Africa under the supervision of Arthur. H. Winckers & Associates Mineral Processing Consulting.
Mr. Arthur Winckers, P.Eng., Consulting Mineral Processing Engineer for Hana is the qualified person as defined in NI 43-101 and has reviewed the technical information in this press release.
About Hana Mining's Ghanzi Copper-Silver Project in Botswana:
The Ghanzi Project is located in the center of the Kalahari Copper Belt in northwestern Botswana. The Ghanzi property covers 2,169 sq Km, and contains sediment-hosted copper-silver deposits with a demonstrated cumulative tested strike length of 70 kilometres. This favorable geology extends over an estimated strike length of 600 kilometres. Hana Mining released results of its most recent NI 43-101 compliant resource estimate for the Ghanzi Project on April 21, 2010, announcing an inferred mineral resource of 3.9 billion pounds of copper and 62.1 million ounces of silver from 177 million tonnes. This mineral resource estimate consists of 73.5 million tonnes grading 1.5% Cu and 19 g/t Ag in the Banana Zone, 13.4 million tonnes grading 1.7% Cu and 12 g/t Ag in Zone 5, 6.3 million tonnes grading 1.5% Cu and 7 g/t Ag in Zone 6; all at a cut-off grade of 0.75% Cu. Also included is 83.6 million tonnes grading 0.46% Cu and 3.6 g/t Ag at a cut-off grade of 0.30% in the Chalcocite Zone.
The Banana Zone exhibits certain areas of higher grade Cu and Ag mineralization, particularly between sections 49700 to 52000 on the North limb and sections 63000 to 71000 on both the North and South limbs, which represent an opportunity to locate starter pits and mine initial tonnages at higher than average grades. These higher grade pockets tend to be well within open pit depth parameters and represent opportunities to improve early cash flow and overall returns in development.
The project will benefit from proposed rail and power infrastructure expansions, along with proximity to local population centers and workforce. A feasibility study is currently underway (funded by the World Bank and the governments of Botswana and Namibia) to support completion of a rail line link that would connect Botswana with the Namibian port of Walvis Bay, on the Atlantic coast. The closest existing railhead to port is at Gobabis, in Namibia, approximately 550 km from our property. Construction has begun on the 600MW expansion of the government-owned Moropule Power Plant, having secured US$825 million project funding in May 2009. The Ghanzi Copper-Silver Project is currently accessed by the paved Trans-Kalahari highway, which passes within 15 km of the property.
The Ghanzi property is one of Africa's premier future copper-silver resources.
Source: Hana Mining Ltd.