Batero Gold Reports Preliminary Oxide Resource Potential and Metallurgical Test Results
As part of Batero's planned 2012 work program to evaluate the potential of a high grade development option at the La Cumbre porphyry deposit in the southern area of the [wp=1397]mineral resources, the Company will evaluate the opportunity to improve project economics through low cost heap leach mineral processing and will advance metallurgical test work and deposit modeling to increase oxide resources, gold grade and recovery.
Oxide Mineral Resources and Initial Metallurgy Highlights:
-- Zones of higher grade oxide resources, grading over 1 g/t gold near
surface at La Cumbre and grading 11.42 g/t gold over 5.8 metres adjacent
to the deposit, remain open to delineate
-- Initial metallurgical test work on oxide gold mineralization returned up
to 94% recovery;
-- Oxide gold resources (at a 0.16 g/t gold cut off):
-- 313,000 ounce indicated resource in 18 M tonnes averaging 0.54 g/t
gold
-- 275,000 ounce inferred resources in 24 M tonnes averaging 0.36 g/t
gold
-- Oxide mineral resources amenable to low cost heap leach processing
represent approximately 10% of the current indicated and inferred
resources at the Project at this preliminary stage
-- Areas of oxide mineralization adjacent to La Cumbre still need to be
modelled into the oxide portion of the oxide resource estimate potential
-- Mineralization in the oxide horizon and the thicker, underlying
transition horizon at La Cumbre will be further evaluated to increase
the potential leachable gold resource
View Figure 1 - Gold Grades Section 5300: http://file.marketwire.com/release/bat322_F1.pdf
Figure 2 - Gold Grades - within Gold Envelope and 0.16 cut-off Gold Whittle Pit Shell - 1525 m Bench: http://media3.marketwire.com/docs/bat322_F2.pdf
Figure 3 - Sulphur Grades Section 5300: http://media3.marketwire.com/docs/bat322_F3.pdf
Table 1: Summary Cyanide Leach Test Results and Table 2: Preliminary Oxide and Sulphide Resource Potential
"We are pleased that 10% of our initial mineral resources are classified as oxide mineralization that may be amenable to low cost heap leaching. Preliminary metallurgical testing also shows high recoveries of up to 94% in the oxide material," stated Brandon Rook, President and CEO of the Company. "An objective of our 2012 work program will be growth of the oxide opportunity at La Cumbre to contribute positively to the PEA. Further modeling and metallurgical test work will be completed in 2012 to determine if there is a variation in gold recoveries between the oxide and the transition zones or if these two zones can be treated together. Also, further drill testing of the oxide zone has the potential to increase the volume of the oxide resources through new discoveries and better definition."
Potentially Significant Volume of Oxidized Mineralization may be Amenable to Low Cost Heap Leaching
The presence and thickness of the oxide mineralization and underlying transition mineralization at La Cumbre are such that an initial heap leach extraction scenario might be a viable option. At surface to a preliminary depth of 70 metres at the La Cumbre deposit is a higher grade gold-bearing "oxide mineral zone". Below the oxide zone is a thicker "transition mineral zone", over a vertical distance of 150 metres to 200 metres, which overlies the primary "sulphide mineral zone".
The thick transition zone, with low sulphur content, requires additional metallurgical test work to be included in, and therefore increase, the oxide mineral resources of the Project (Figure 3 - http://media3.marketwire.com/docs/bat322_F3.pdf). Test work will also determine the gold and silver recovery for oxide and transition mineralization. The histograms in Figure 3 show the sulphur grades and the variation within the oxide, transition and sulphide zones at La Cumbre. In general, the lowest sulphur grade produces the highest gold recovery.
Significant Zones of Higher Grade Oxide Mineralization
At La Cumbre, higher grade gold mineralization, averaging over 1 g/t gold, is situated near surface and adjacent to the deposit, and has the potential to improve the economics in the early stages of the Project (Figure 1 - http://file.marketwire.com/release/bat322_F1.pdf and Figure 2 - http://media3.marketwire.com/docs/bat322_F2.pdf). Additionally, high grade epithermal gold mineralization, in oxide and capped at 3 g/t gold in the resource estimate, has been intersected near surface and adjacent to La Cumbre. Drill hole LC003 intersected 43.40 g/t gold over 2 metres at 28 metres down hole. Drill hole QAP034, located northeast of La Cumbre, grades 11.42 g/t gold over 5.80 metres from 9.7 metres down hole. Further delineation is required to determine the extent of this oxide mineralization.
Pockets of higher grade gold mineralization are situated throughout the mineral resources at La Cumbre (Figure 1 -http://file.marketwire.com/release/bat322_F1.pdf). The contours in Figure 1 show the gold grade contours as modeled in Leapfrog 3D software and their variation within the oxide, transition and sulphide zones at La Cumbre. In general, the highest gold grades produce the highest recovery.
Superior Recovery with Cyanidation
Preliminary metallurgical testing undertaken by G&T Metallurgical Services ("G&T") on behalf of the Company was completed on six drill core composite samples to determine their response to gravity concentration, flotation and cyanidation. The response to cyanidation via bottle roll tests was clearly superior and yielded gold recoveries ranging from 66% to 94% as determined by G&T. Test work on oxide mineralization returned up to 94% recovery.
Preliminary metallurgical tests indicate a relationship between gold and sulphur grades, and the gold recovery (Table 1). Cyanidation extraction (after 48 hours) averaged 73% recovery at a nominal P80 grind size of 100 microns, and 80% recovery at a finer nominal grind size of 70 microns. The best gold recovery was on the highest grade, with 91% recovery at the coarser grind size and 94% recovery at the finer grind size. The lowest sulphur grade produced the highest recovery.
Recovery Increases with Flotation and Cyanidation
A second phase of metallurgical testing was completed on three of the samples representing the sulphide zone from the previous test work. Three batch cleaner tests were carried out as well as cyanide bottle roll tests on the rougher and cleaner tails. A 5% to 10% increase in gold recovery using flotation and cyanidation of the rougher and cleaner tails was achieved on a nominal 100 micron grind and a 4% increase in gold recovery was achieved on a nominal grind of 70 microns.
Further Metallurgical Testing for Potential Improvement in Recovery
The next stage of metallurgical testing, as recommended by RPA, should investigate means for improving cyanidation recovery including pre-aeration, aeration under leach, lead nitrate addition, and varying cyanide concentration and grind conditions. A variability test program will be undertaken to better understand the relationship between gold and sulphur grades with respect to gold recovery. Additional testing also will include a gold deportment study, heap leach test work on oxide material and an economic capital cost analysis for two grind scenarios.
The mineral resource estimate and other scientific and technical information contained in this news release were prepared by or under the supervision of Paul Chamois, M.Sc. (applied), P.Geo., and Luke Evans, M.Sc., P.Eng., of Roscoe Postle Associates Inc., who are independent Qualified Persons under National Instrument 43-101.
ON BEHALF OF THE BOARD OF BATERO GOLD CORP.
Brandon Rook, President & CEO
Batero Gold Corp.
FORWARD-LOOKING STATEMENTS: Certain of the statements and information in this press release constitute "forward-looking statements" or "forward-looking information" Any statements or information that express or involve discussions with respect to predictions, expectations, beliefs, plans, projections, objectives, assumptions or future events or performance (often, but not always, using words or phrases such as "expects", "anticipates", "believes", "plans", "estimates", "intends", "targets", "goals", "forecasts", "objectives", "potential" or variations thereof or stating that certain actions, events or results "may", "could", "would", "might" or "will" be taken, occur or be achieved, or the negative of any of these terms and similar expressions) are not statements of historical fact and may be forward-looking statements or information.
Forward-looking statements or information relate to, among other things: the timing and scope of expected diamond drilling; resource estimate, grades on the Batero-Quinchia project; scope of mineralization within the Batero-Quinchia project; timing of receipt of permits and regulatory approvals; the sufficiency of the Company's capital to finance the Company's operations; geological interpretations and potential mineral recovery processes.
Forward-looking statements or information are subject to a variety of known and unknown risks, uncertainties and other factors that could cause actual events or results to differ from those reflected in the forward-looking statements or information, including, without limitation, risks relating to: fluctuations in the spot and forward price of gold or certain other commodities; changes in national and local government legislation, taxation, controls, regulations and political or economic developments in Canada, Colombia or other countries in which the Company may carry on business in the future; the uncertainties involved in interpreting geological data; business opportunities that may be presented to, or pursued by, the Company; operating or technical difficulties in connection with mining activities; the speculative nature of gold exploration and development, including the risks of obtaining necessary licenses and permits; diminishing quantities or grades of reserves; and contests over title to properties, particularly title to undeveloped properties. In addition, there are risks and hazards associated with the business of gold exploration, development and mining, including environmental hazards, industrial accidents, unusual or unexpected formations, pressures, cave-ins, flooding and gold bullion losses (and the risk of inadequate insurance, or the inability to obtain insurance, to cover these risks).
This list is not exhaustive of the factors that may affect any of the Company's forward-looking statements or information. Forward-looking statements or information are statements about the future and are inherently uncertain, and actual achievements of the Company or other future events or conditions may differ materially from those reflected in the forward-looking statements or information due to a variety of risks, uncertainties and other factors, including, without limitation, those referred to in the Company's Filing Statement dated as of June 22, 2010 under the heading "Risk Factors". Although the Company has attempted to identify important factors that could cause actual results to differ materially, there may be other factors that cause results not to be as anticipated, estimated, described or intended. Accordingly, readers should not place undue reliance on forward-looking statements or information.
The Company's forward-looking statements and information are based on the assumptions, beliefs, expectations and opinions of management as of the date of this press release, and other than as required by applicable securities laws, the Company does not assume any obligation to update forward-looking statements and information if circumstances or management's assumptions, beliefs, expectations or opinions should change, or changes in any other events affecting such statements or information. For the reasons set forth above, investors should not place undue reliance on forward-looking statements and information.
Cautionary Note Regarding Mineral Resources and Mineral Reserves
Readers are advised that National Instrument 43-101 of the Canadian Securities Administrators requires that each category of mineral reserves and mineral resources be reported separately. Readers should refer to the Company's current technical reports and other continuous disclosure documents filed by the Company, available on SEDAR at www.sedar.com for further information the mineral resource estimates of the Company's projects, which are subject to the qualifications and notes set forth therein, as well as for additional information relating to the Company more generally.
Mineral resources which are not mineral reserves, have a great amount of uncertainty as to their existence and do not have demonstrated economic or legal viability. Inferred mineral resources have insufficient confidence to allow the meaningful application of technical and economic parameters or to enable an evaluation of economic viability suitable for public disclosure. Neither the Company, nor readers, can assume that all or any part of an inferred mineral resource will be upgraded to indicated or measured mineral resources. Most projects at the inferred mineral resource stage do not ever form the basis of feasibility or other economic studies, or achieve successful commercial production. Each stage of a project is contingent on the positive results of the previous stage and that there is a significant risk that the results may not support or justify moving to the next stage.
Table 1: Summary Cyanide Leach Test Results
Sample Grind Grade Recovery - 48 hrs CN Lime
(um P80) (g/t Au) (%) (kg/t) (kg/t)
----------------------------------------------------------------------------
101 91 0.4 7.7
MMLC-004 1.17
71 94 0.5 7.0
----------------------------------------------------------------------------
97 72 1.3 3.1
MMLC-005 0.79
71 76 1.5 3.1
----------------------------------------------------------------------------
99 66 0.5 2.2
MMLC-010 0.66
72 68 0.7 1.5
----------------------------------------------------------------------------
98 66 0.5 1.8
MMLC-011 0.58
67 82 0.7 1.1
----------------------------------------------------------------------------
94 69 0.4 2.1
MMLC-012 0.65
59 84 0.5 1.0
----------------------------------------------------------------------------
101 75 0.5 1.4
MMLC-014 0.78
68 76 0.7 1.2
----------------------------------------------------------------------------
98 73
Average 0.77 0.7 2.8
68 80
----------------------------------------------------------------------------
Table 2: Preliminary Oxide and Sulphide Resource Potential
"Oxide Zone" - Indicated at 0.16 g/t Au Cut-Off
Tonnes Cu Gold
Area (Mt) Au (g/t) Ag (g/t) (%) (000 oz)
----------------------------------------------------------------------------
La Cumbre 15.4 0.56 1.73 0.08 275
Dos Quebradas 2.8 0.42 1.75 0.07 37
Total 18.2 0.54 1.73 0.08 313
"Sulphide Zone" - Indicated at 0.16 g/t Au Cut-Off
Tonnes Cu Gold
Area (Mt) Au (g/t) Ag (g/t) (%) (000 oz)
----------------------------------------------------------------------------
La Cumbre 188.5 0.43 1.5 0.08 2,597
Dos Quebradas 41.8 0.47 1.61 0.08 637
Total 230.3 0.44 1.52 0.08 3,234
"Oxide Zone" - Inferred at 0.16 g/t Au Cut-Off
Tonnes Cu Gold
Area (Mt) Au (g/t) Ag (g/t) (%) (000 oz)
----------------------------------------------------------------------------
La Cumbre 6.7 0.37 1.66 0.05 81
El Centro 13.3 0.32 1.85 0.06 138
Dos Quebradas 3.8 0.46 1.7 0.06 56
Total 23.9 0.36 1.77 0.06 275
"Sulphide Zone" - Inferred at 0.16 g/t Au Cut-Off
Tonnes Cu Gold
Area (Mt) Au (g/t) Ag (g/t) (%) (000 oz)
----------------------------------------------------------------------------
La Cumbre 67.3 0.38 1.32 0.05 824
El Centro 122.3 0.28 2.14 0.07 1,093
Dos Quebradas 28.8 0.43 1.48 0.06 395
Total 218.4 0.33 1.8 0.06 2,313
Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
Contacts:
Batero Gold Corp.
604.568.6378
604.568.6834 (FAX)[/wp]
info@baterogold.com
www.baterogold.com