Boxxer announces preliminary metallurgical test work results
Leach Test Results:
Un-optimized leach tests using a standard bottle roll methodology were performed to determine the metal recoveries using an acid leach for copper and subsequent cyanide leach for gold-silver-platinum-palladium. Results of the leach tests are as follows:
a) Copper recovery during the first two hours of the leach tests was 90%
in the Oro Amigo sample and 95.7% in the Boss Mine sample. As the
leach test progressed, the copper in solution re-precipitated into
the residue of the acid leach stage and percentage copper recovery
declined to 36.7% in the Oro Amigo sample and 35.2% in the Boss Mine
sample
b) Over a 24 hour period 92.2% of the gold, 79.9% of the palladium,
45.4% of the platinum and 37.3% of the silver was recovered in the
Oro Amigo sample and 94.2% of the gold, 76.3% of the palladium, 50.1%
of the platinum and 70% of the silver was recovered from the Boss
Mine sample.
Flotation Test Results:
Based on the mineral suite present, conventional flotation of copper sulphides and carbonates into a concentrate would be the most logical process for extraction of copper. This process would also capture gold-silver-platinum-palladium as a by-product metal value in the concentrate. Results of the flotation tests are as follows:
a) The rougher test results failed to recover significant amounts of
copper, gold, platinum and palladium into a rougher concentrate. The
copper recovery into the cumulative rougher concentrate averaged 25%
for the Boss Mine sample and 36% for the Oro Amigo sample.
b) Gold recovery averaged 32% for the Boss Mine sample and 43% for the
Oro Amigo sample, and
c) Flotation does not appear to be an attractive process for metal
recovery. Significantly more development and study would be required
to determine the causes of poor flotation performance.
Details of Metallurgical Test Work
The test work on the two representative samples of oxidized copper-gold mineralization from the Boss Mine and the Oro Amigo Mine was completed by G&T Metallurgical Services ("G&T"), a leader in providing mineral processing and analytical services to the mining industry, at their laboratories in Kamloops, British Columbia,
Mineralogy:
The main copper mineral is malachite (copper-oxide) with minor amounts of chalcopyrite, chalcocite, covellite and cuprite. Gangue minerals include magnetite, hematite, pyrite and goethite.
Head Grades:
The analytical results for the head samples for the flotation test work are summarized below.
-------------------------------------------------------------------------
Sample Copper Gold Silver Molybdenum Platinum Palladium
Zone No. (%) (g/t) (g/t) (%) (g/t) (g/t)
-------------------------------------------------------------------------
Boss Mine 1 1.16 0.50 11.00 0.01 0.13 0.35
2 1.19 0.43 8.00 0.00 0.11 0.32
average 1.18 0.47 10.00 0.01 0.12 0.33
-------------------------------------------------------------------------
Oro Amigo 1 1.29 0.67 3.00 0.00 0.16 0.38
2 1.30 0.63 3.00 0.00 0.19 0.39
average 1.30 0.65 3.00 0.00 0.18 0.39
-------------------------------------------------------------------------
Mineral Fragmentation:
The samples used in the flotation test work were crushed to at least 80% passing 150 mesh to liberate the mineralization from the sample. Based on this test work, 37% of the malachite was liberated in the Boss Mine sample and 69% of the malachite was liberated from the Oro Amigo sample. Preliminary indications are that reducing the primary grind size could liberate more of the copper mineralization from the samples.
Ore Hardness:
Ore hardness was determined using a standard Bond Ball Mill Work Index ("BMWI") measured in kilowatts required per tonne of material processed. The BMWI for the Boss Mine sample was determined to be 11.7 kWh/tonne at a nominal 76 microns and 17.2 kWh/tonne for the Oro Amigo sample at a nominal 71 microns. The average hardness BMWI of porphyry copper deposits is about 15 kWh/tonne.
Metallurgical Test Work Procedures
The representative sample for the Boss Mine weighed 85.1 kilograms ("kg") and the representative sample of the Oro Amigo mine weighed 44.5 kg. The representative samples were staged crushed to pass 6 mesh, homogenized and rotary split into 2 kg charges. Representative head samples were assayed for elements of interest (see Head Grades above).
The representative samples were initially tested using a conventional flotation process. Based on the mineral suite present, flotation of copper sulphides and carbonates into a concentrate would be the most logical process for extraction of copper. This process would also capture gold-silver-platinum-palladium as a by-product metal value in the concentrate.
For the leach tests, the Boss Mine sample was ground to 80% passing 149 microns ("(micro)m"). The Oro Amigo sample was ground to 80% passing 144 (micro)m. A 500 gram sub-sample from each sample was selected to which 1,000 milliliters of water was added. The samples were transferred to separate bottles and alkaline cyanide solution with lime was added. The cyanide concentration was 1,000 parts per million at a pH level of 11. The mixing of the solution and the sample created a slurry that consisted of 33% solids by weight. The samples were continuously leached for 24 hours. Aliquots of solution were collected after 2, 6, and 24 hours. The solids were filtered, dried, weighed, and assayed along with the solution samples. Acid consumption was 21.2 kg/tonne for the Boss Mine sample and 51 kg/tonne for the Oro Amigo sample. Cyanide consumption was 11.2 kilograms per tonne for the Boss mine sample and 12.7 kilograms/tonne for the Oro Amigo sample. Lime consumption for the Boss Mine sample was 1.1 kg/tonne and 1.3 kg/tonne for the Oro Amigo sample. G&T Metallurgical Services Ltd is independent of Boxxer.
Elmer B. Stewart, MSc. P. Geol., President of Boxxer, is the Corporation's nominated Qualified Person pursuant to National Instrument No.43-101, Standards for Disclosure for Mineral Projects, has reviewed the technical information disclosed in this news release.
About Boxxer Gold Corp.
Boxxer Gold is a Canadian junior resource company involved in the exploration of three copper-gold projects in the state of Nevada, and a shear hosted gold project located 110 kilometres north of Yellowknife NWT,
Neither TSX Venture Exchange nor its Regulation Services Provider (as
that term is defined in the policies of the TSX Venture Exchange) accept
responsibility for the adequacy or accuracy of this release.
Forward-Looking Statements: This news release may contain certain forward-looking information. All statements included herein, other than statements of historical fact, are forward-looking information and such information involves various risks and uncertainties. There can be no assurance that such information will prove to be accurate, and actual results and future events could differ materially from those anticipated in such information. A description of assumptions used to develop such forward-looking information and a description of risk factors that may cause actual results to differ materially from forward-looking information can be found in the company's disclosure documents on the SEDAR website at www.sedar.com. The company does not undertake to update any forward-looking information except in accordance with applicable securities laws.
%SEDAR: 00019646E
For further information: on Boxxer please visit our website at www.boxxergold.com or contact: Elmer B. Stewart, President & Chief Executive Officer, Tel: (403) 264-4811, Cel: (403) 680-9584, e-mail: [email protected]; John L. Maslanyk, Vice President & Chief Information Officer, Tel: (403) 804-2251, Toll Free: 1-888-479-3596, e-mail:[email protected]; Alison Tullis, Senior Account Manager, Tel: (416) 868-1079 ext. 233, Fax: (416) 868-6198, e-mail: [email protected]
Share this article