Hana Announces Exceptional Silver Recoveries From Oxide-Transitional Material at the Banana Zone
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VANCOUVER, BRITISH COLUMBIA -- (Marketwire) -- 10/03/11 -- Hana Mining Ltd. ('Hana' or the 'Company') (TSX VENTURE: HMG)(FRANKFURT: 4LH) is pleased to announce final results on the first locked cycle tests on oxide-transitional material from the Banana Zone at the Ghanzi Project. The results show that the copper-silver oxide mineralization at the Banana Zone is amenable to conventional flotation recovery technology (Table 1).
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Table 1. Ghanzi Project - Banana Zone Oxide Locked Cycle Test-1 Results
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Concentrate
Grade %, g/t Recovery %
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Mass Cu Ag Cu Ag
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(%) (%) (g/t) (%) (%)
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Flotation Feed 100 1.63 15.00 100 100
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Bulk Concentrate 1.7 48.1 764.00 49.9 87.7
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Bulk 1st Cleaner Tail 7.5 1.53 6.00 7.1 3.1
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Bulk Rougher Tail 90.8 0.78 2.00 43.1 9.2
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Highlights of recent metallurgical results:
-- Initial locked cycled tests on a master composite sample, containing
both oxide and transition material, at a coarse grind size of 143
microns, show a copper recovery of 49.9% and an exceptionally high
silver recovery of 87.7%.
-- A final concentrate grade of 48.1% copper and 764.0 g/t silver was
achieved at the above stated recoveries.
-- The metallurgical work on the master composite, prepared to represent
typical oxide and transition ore mineralization, demonstrates that it is
possible to co-process this type of mineralization with the Ghanzi
copper sulphide mineralization without a detrimental effect by using
similar processing conditions.
-- Characterization of samples of oxide and oxide to sulfide transition
mineralization, is ongoing so as to determine the effect of the
variability in copper mineralization on the metallurgical response.
Discussion of Results:
The preliminary metallurgical testing program was designed to determine the grinding and flotation response of a Banana Zone oxide-transition mineralization sample which is typical of the oxide-transition ore mineralization included in the current Ghanzi NI 43-101 compliant resource estimate (Figure 1). On November 8, 2010, the company released the metallurgical results on sulphide material from the Banana Zone. 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 in 2012.
To view Figure 1, visit the following link: http://media3.marketwire.com/docs/HANAlocationMap.pdf
The master composite on which the test work was performed was constructed from 21 samples selected from 14 diamond drill holes located in the New Discovery, Northeast Fold and South Limb areas (Table 2).
The master composite which represents from about 100 metres of core length is considered to be typical of the copper oxide transition zone mineralization at the Banana Zone.
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Table 2. Banana Zone Oxide-Transition Composite
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Zones Hole-ID From (m) To (m) Total (m)
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New Discovery HA-122b-D 28.5 32.5 4.0
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New Discovery HA-128c-D 38.0 43.0 5.0
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New Discovery HA-128c-D 52.0 60.0 8.0
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New Discovery HA-134-D 33.0 40.0 7.0
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New Discovery HA-160-D 25.0 31.0 6.0
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New Discovery HA-160-D 31.0 38.0 7.0
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New Discovery HA-160-D 52.0 56.5 4.5
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Northeast Fold HA-165-D 36.0 42.0 6.0
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Northeast Fold HA-176-D 26.6 37.0 10.4
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Northeast Fold HA-176-D 37.0 41.0 4.0
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Northeast Fold HA-176-D 41.0 45.0 4.0
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Northeast Fold HA-177-D 37.0 41.0 4.0
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Northeast Fold HA-177-D 41.0 49.0 8.0
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South Limb HA-200-D 49.3 55.0 5.7
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South Limb HA-202-D 54.0 59.0 5.0
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South Limb HA-211b-D 43.7 48.0 4.3
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South Limb HA-218-D 27.0 32.0 5.0
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South Limb HA-223-D 40.2 46.0 5.8
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South Limb HA-224-D 40.4 44.0 3.6
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South Limb HA-227-D 58.7 63.8 5.1
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South Limb HA-229-D 34.4 43.0 8.6
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Total 121.0
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Mineralogical work undertaken on the master composite revealed about 35% of the feed copper is present in chrysocolla, an unfloatable copper-silicate mineral. About 25% of the feed copper is also present in copper oxide minerals, malachite and azurite; the balance is present as copper sulfide minerals.
The copper feed grades, in the suite of samples constructed for floatation testing, ranged from about 0.4% to 12.7%. The copper feed grade in the master composite, the subject of this press release, was 1.63% copper. An acid soluble copper assay on the master composite revealed that about two thirds of the feed copper present in the sample is acid soluble. About one third is soluble in sodium cyanide solution, indicating the presence of secondary copper sulphide minerals.
The sulphide sulphur content was generally quite low in the samples, ranging from less than 0.1% to 1.89%. The sulphide sulphur content in the master composite was only 0.17%.
Initial locked cycled metallurgical tests on the oxides and transitional material from the Banana Zone show that the sample tested is amenable to conventional flotation methods resulting in a copper recovery of 49.9%, and a silver recovery of 87.7%. The testing also showed that conventional flotation can produce a relatively high grade concentrate, with average grades of 48.1% copper and 764 g/t silver. The flotation response of the oxide-transition ore mineralization will be a function of the copper mineralization which varies across the zone as indicated by the results of mineralogy studies e.g. the 50 percent total copper recovery achieved in the test work was achieved from the recovery of 95 percent of the contained copper sulfides and 30 percent of the contained copper oxide minerals.
The results of this test work compare to the results of previous metallurgical work carried out on a composite of copper sulphide mineralization material from the Banana Zone which yielded a copper recovery of 92.75% and a silver recovery of 80.58% resulting in an average concentrate grade of 43.55% copper and 853.57 g/t silver (Please see the press release dated November 8, 2010).
For comparison, most conventional sulphide projects in southern Africa have concentrate grades between 22% to over 50% copper. The Kupferschiefer copper deposits in Poland and Germany, which are analogous to copper deposits at the Ghanzi Project, have an average concentrate grade of 23% copper. Therefore, the Banana Zone will produce a very high quality product that should elicit considerable interest from global copper smelters.
Development Update:
The following engineering and consultation activities are ongoing to fulfill the goal of completion of a Preliminary Economic Assessment ('PEA') in 2012:
-- Work has resumed on the PEA. The company will release more information
regarding the timing of completion of the PEA within the next few weeks.
-- Resource modeling is progressing as expected and a NI 43-101 compliant
resource estimate for the Banana Zone is expected in 2012. The company
will release more information regarding the timing of completion of the
resource estimate within the next few weeks.
-- The 2011 infill drilling program, which is budgeted at 40,000 metres is
progressing as expected. The company will continue to release results
from the drilling program as they are made available to the company.
-- Hana is well financed with approximately $16.4 million in cash on hand.
Hana Mining's CEO and Chairman, Marek Kreczmer, commented as follows:
'Again the metallurgical work demonstrates that a conventional mining and milling operation at the Banana Zone will produce a very high-grade high-quality product (concentrate) which should elicit considerable interest from smelters. I was also pleasantly surprised with the metallurgical results from the oxide-transitional material from the Banana Zone which shows exceptionally high silver recoveries. We have also confirmed that oxide-transitional material from the Banana Zone can be blended with sulphide material which should reduce handing costs, as opposed to having to separate the oxide-transitional material from sulphide material when we are mining the Banana Zone.'
Qualified Person and Quality Assurance/Quality Control
Metallurgical test work was carried out by G&T Metallurgical Services Ltd. of Kamloops, British Columbia, Canada 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 2,149 square kilometres, 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 December 20, 2010, announcing an Indicated mineral resource of 762 million pounds of copper and 16 million ounces of silver from 37.4 million tonnes at a grade of 0.93% copper and 13.4 g/t silver. All of the Indicated resources are from the Banana Zone. There are also Inferred resources of 5.6 billion pounds of copper and 85.4 million ounces of silver from 423.9 million tonnes. This Inferred mineral resource estimate consists of 225.4 million tonnes grading 0.64% Cu and 8.1 g/t Ag in the Banana Zone, 20.7 million tonnes grading 1.23% Cu and 8.7 g/t Ag in Zone 5, 16.7 million tonnes grading 0.86% Cu and 4.0 g/t Ag in Zone 6, and 161.1 million tonnes grading 0.45% Cu and 3.6 g/t Ag in the Chalcocite Zone; all at a cut-off grade of 0.30% Cu.
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.
Statements in this press release, other than purely historical information, including statements relating to the Company's future plans and objectives or expected results, may include forward-looking statements. Forward-looking statements are based on numerous assumptions and are subject to all of the risks and uncertainties inherent in resource exploration and development. As a result, actual results may vary materially from those described in the forward-looking statements.
The TSX Venture Exchange has not reviewed and does not accept responsibility for the adequacy or accuracy of this release.
Contacts:
Hana Mining Ltd.
Marek Kreczmer
CEO
(604) 676-0824
info@hanamining.com
Hana Mining Ltd.
Patrick Donnelly
VP - Corporate Development
(604) 676-0824
(778) 370-0146 (FAX)
patrick@hanamining.com
www.hanamining.com