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OTTAWA,
ONTARIO--(Marketwire - Dec. 8, 2009) - Orezone Gold Corporation
(TSX:ORE) is pleased to report the final column test results on its
100% owned Bombore gold deposit located in Burkina Faso, West Africa. The
final test results for the near surface oxide and mixed oxide/sulphide
(transition) resources are better than the interim results announced on
October 14, 2009.
Metallurgical Highlights
Column Leach Test
-- 82% weighted gold recoveries for the oxide and 80% for the transition resources after 44 days of leaching (see Table 1); -- Cyanide consumption of 0.19 kg/t for the oxide and 0.43 kg/t for the transition resources; -- Recent Agglomeration Optimization: 3 kg/t cement for the transition and 7 to 8 kg/t for the oxide resources, depending on rock type. Initial testing using 9 kg/t cement for the oxide resource yielded good flow rate and fair to excellent pellet condition after 44 days (see Table 2).
These
results indicate that the projected processing costs could be reduced
by a further 17% for the oxide and 9% for the transition material from
what was estimated based on the initial results announced on October
14, 2009.
Drilling Programs
Although the Company's primary focus is the expansion of the oxide and
transition resources, a six hole 3,000 m diamond drill program is
underway to test the geological model to a depth of 300 m below four
pit shells. The program will be completed by year-end with results
expected to be announced during the first quarter of 2010.
In 2010, the Company will carry out a $3 Million delineation drill
program to both increase and upgrade the oxide and transition
resources. This drill program will be completed by the end of the
second quarter. Updated scoping study results and a baseline study of
the project foot print will be released in the first quarter. The
Company is continuing to study power costs for grinding and processing
of the sulphide resource using conventional milling techniques as they
may provide additional upside for the development of the project beyond
a heap leach operation.
Table 1 Summary of Bombore Column Test Results
------------------------------------------------------------------------- Sample ID AM31 AM32 AM21 AM22 ------------------------------------------------------------------------- Oxide Transition material material excluding Oxide excluding Transition Description metasediments metasediments metasediments metasediments ------------------------------------------------------------------------- Proportion of heap leachable resource 48.6% 16.6% 25.9% 8.8% ------------------------------------------------------------------------- Expected Gold Grade (g/t) 0.61 0.65 0.62 0.59 ------------------------------------------------------------------------- Head assays (g/t) 0.63, 0.74 1.52, 0.80 0.61 0.59 ------------------------------------------------------------------------- Back-calculated head assays (g/t) Coarse bottle-roll cyanidation 0.74 0.76 0.69 0.60 Column leaching test 0.69 0.80 0.61 0.58 ------------------------------------------------------------------------- Column Leaching Indicated Gold Recovery after 44 days of leaching (%) 82.7% 80.4% 77.3% 87.5% NaCN consumption after 44 days of leaching (kg/t) 0.14 0.32 0.39 0.54 Column diameter (mm) 190 190 190 190 Column height (mm) 1,433 1,391 1,244 1,291 Final slumpage (%) 3.6% 8.5% 9.3% 11.0% Pellet quality after 44 days Excellent Excellent Fair Fair Flow rate after 44 days (litre/sq. m/hr) 6,396 4,586 4,266 4,338 Recovered grade (g/t) 0.57 0.64 0.47 0.51 Leach tails grade (g/t) 0.12 0.16 0.14 0.07 Portland cement addition (kg/t) 9 9 3 3 ------------------------------------------------------------------------- Optimal cement addition (kg/t) 7 8 3 3 ------------------------------------------------------------------------- ------------------------------------------------------------------------- Sample ID Oxide Transition ------------------------------------------------------------------------- Description Weighted Weighted ------------------------------------------------------------------------- Proportion of heap leachable resource 65.2% 34.7% ------------------------------------------------------------------------- Expected Gold Grade (g/t) ------------------------------------------------------------------------- Head assays (g/t) ------------------------------------------------------------------------- Back-calculated head assays (g/t) Coarse bottle-roll cyanidation Column leaching test ------------------------------------------------------------------------- Column Leaching Indicated Gold Recovery after 44 days of leaching (%) 82.1% 79.9% NaCN consumption after 44 days of leaching (kg/t) 0.19 0.43 Column diameter (mm) Column height (mm) Final slumpage (%) Pellet quality after 44 days Flow rate after 44 days (litre/sq. m/hr) Recovered grade (g/t) Leach tails grade (g/t) Portland cement addition (kg/t) ------------------------------------------------------------------------- Optimal cement addition (kg/t) 7.30 3.00 -------------------------------------------------------------------------
The Bombore gold deposit hosts 0.93 Million
ounces of Indicated resources and 1.78 Million ounces of Inferred
resources at an average gold grade of approximately 0.5 g/t in the near
surface oxide zone and 1.0 g/t in the underlying primary sulphide
resource. Approximately half of the inferred resource is oxide and
transition material amenable to heap leach processing.
The Bombore property has the potential to host a large, open pit gold
project with very good infrastructure in place compared to many
projects in West Africa as it is located just 80km east of the capital
city of Ouagadougou and adjacent to a major national highway, near a
large water reservoir, and accessible to an international power grid
expected to be constructed in the near future.
Dr. Pascal Marquis, Vice President of Exploration for Orezone,
supervised the metallurgical sampling program. Alex Mitchell, Principal
Metallurgist with GBM Minerals Engineering Consultants Limited,
designed and supervised the test work program. The test work was
performed by AMMTEC laboratory in Perth, Australia. The samples sent to
AMMTEC were selected to be representative of the various grades and
rock types for 85% of the Bombore gold resources. Mr. Mitchell and Dr.
Marquis are both Qualified Persons under National Instrument 43-101 and
approved the technical information in this release.
Table 2 Summary of Bombore Agglomeration Optimization Test Results
------------------------------------------------------------ Cement added Crush size (P100) Flow rate Pellet Quality kg/t mm L/m2/hr ------------------------------------------------------------ AM21 - Mixed material 3 15 13,571 Good ------------------------------------------------------------ (i)3 15 4,266 Fair ------------------------------------------------------------ 6 15 18,360 Very good AM22 - Mixed material 3 15 14,245 Good ------------------------------------------------------------ (i)3 15 4,338 Fair ------------------------------------------------------------ 6 15 19,420 Very good AM31 - Oxide material 6 25 10,906 Poor/fair ------------------------------------------------------------ 7 25 16,153 Good ------------------------------------------------------------ 8 25 16,210 Good ------------------------------------------------------------ (i)9 25 6,396 Excellent AM32 - Oxide material 6 25 4,938 Poor/fair ------------------------------------------------------------ 7 25 4,707 Poor ------------------------------------------------------------ (i)8 25 13,307 Good/Fair ------------------------------------------------------------ 9 25 4,586 Excellent (i)Results of 44-day column leach test ------------------------------------------------------------ Optimal cement dosage ------------------------------------------------------------
Orezone
is a gold exploration and development company with more than 15 years
experience in West Africa, one of the world's fastest growing gold
producing regions. Orezone delineated, developed, financed and sold
Burkina Faso's largest deposit (Essakane) to IAMGOLD for $350M and
continues to focus on developing the rest of its pipeline of advanced
projects including Bombore, one of the largest deposits in Burkina
Faso. Orezone's mission is to create wealth by discovering and
developing gold resources in an efficient and responsible manner for the
benefit of its shareholders and other stakeholders.
FORWARD-LOOKING STATEMENTS AND FORWARD-LOOKING INFORMATION: This news
release contains certain "forward-looking statements" within
the meaning of applicable Canadian securities laws. Forward-looking statements
and forward-looking information are frequently characterized by words
such as "plan," "expect," "project,"
"intend," "believe," "anticipate",
"estimate" and other similar words, or statements that
certain events or conditions "may" or "will" occur.
Forward-looking statements and forward-looking information in this news
release include statements with respect to the scope and timing of the
drilling project and metallurgical testing for Bombore.
Forward-looking statements are based on certain assumptions, opinions
and estimates of management at the date the statements are made, and
are subject to a variety of risks and uncertainties that could cause
actual events or results to differ materially from those projected in
the forward-looking statements. The assumptions include that contracted
parties provide goods and/or services on the agreed timeframes, that
equipment necessary for the drilling program is available as scheduled,
that no labour shortages or delays are incurred, that no material
adverse change occurs to Orezone. Factors that could cause the
forward-looking statements and forward-looking information to differ
materially in actuality include the failure of contracted parties to
perform as contracted and the failure of equipment. The Company undertakes
no obligation to update forward-looking statements if circumstances or
management's estimates or opinions should change. The reader is
cautioned not to place undue reliance on forward-looking statements.
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 annual information form of Orezone for the year ended
December 31, 2008, and other continuous disclosure documents filed by
Orezone since February 25, 2009 available at www.sedar.com, for
this detailed information, which is subject to the qualifications and
notes set forth therein.
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