Aurizon Increases the Hosco In-Pit Measured and Indicated Mineral Resources by 31% at Joanna
VANCOUVER, BRITISH COLUMBIA -- (Marketwire) -- 06/13/11 -- Editors Note: There is one image associated with this Press Release
Aurizon Mines Ltd. (TSX: ARZ)(NYSE Amex: AZK) is pleased to report that an updated mineral resource estimate has been completed for the Hosco deposit at its 100% owned Joanna Property, located 20 kilometres east of Rouyn-Noranda, in north-western Quebec. The updated mineral resource estimate was prepared by SGS Canada Inc. - Geostat ('SGS Geostat') in collaboration with Aurizon's personnel.
The updated mineral resource estimate integrates the results of the drilling program that took place during the last three quarters of 2010 and January 2011 in the lateral and depth extensions of the pit outline of the Hosco Deposit-Joanna Gold Project defined in the Pre-Feasibility Study of December 22, 2009, available under the Company's profile at www.sedar.com. It includes 230 additional new holes.
-- At a cut-off grade of 0.5 grams of gold per tonne, in-pit measured and
indicated mineral resources have increased by 537,000 ounces, a 31%
increase when compared to the last estimate released on July 5, 2010 and
now total 2,245,000 ounces of gold for the Hosco deposit only.
-- In-pit inferred mineral resources stand at 284,000 ounces, a reduction
of 97,000 ounces when compared to July, 2010.
'For the fourth consecutive year, our drilling program has substantially increased the mineral resource base in the Hosco sector of Joanna. These resources will be incorporated into the upcoming Feasibility Study and should have a positive impact on the project,' said Martin Bergeron, P. Eng., Vice-President of Operations.
Table 1: Hosco Deposit - In-Pit Mineral Resources
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May 31, 2011
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Grade Cut-off Category Tonnes Grade
(Au g/t) In-Pit (t) (g/t) Gold (oz)
-----------------------------------------------------------------------
Measured 29,490,000 1.35 1,283,000
0.33 Indicated 25,840,000 1.18 977,000
(Base Case) -----------------------------------------------------
M l 55,330,000 1.27 2,260,000
Inferred 7,730,000 1.15 285,000
-----------------------------------------------------------------------
Measured 28,840,000 1.37 1,275,000
Indicated 25,300,000 1.19 970,000
0.5 -----------------------------------------------------
M l 54,140,100 1.29 2,245,000
Inferred 7,670,000 1.15 284,000
-----------------------------------------------------------------------
Measured 20,460,000 1.60 1,054,000
Indicated 14,710,000 1.47 697,000
1.0 -----------------------------------------------------
M l 35,170,000 1.55 1,750,000
Inferred 4,910,000 1.33 210,000
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July, 2010
----------------------------------------------
Grade Cut-off Category Tonnes Grade Gold Gain/(loss)
(Au g/t) In-Pit (t) (g/t) (oz) (oz)
---------------------------------------------------------------------------
Measured 27,710,000 1.34 1,198,000 85,000
0.33 Indicated 13,460,000 1.22 528,000 449,000
(Base Case) ---------------------------------------------------------
M l 41,170,000 1.30 1,725,000 535,000
Inferred 9,300,000 1.28 383,000 (98,000)
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Measured 26,750,000 1.38 1,186,000 89,000
Indicated 13,050,000 1.25 523,000 447,000
0.5 ---------------------------------------------------------
M l 39,810,000 1.33 1,708,000 537,000
Inferred 9,200,000 1.29 381,000 (97,000)
---------------------------------------------------------------------------
Measured 19,640,000 1.58 995,000 59,000
Indicated 7,990,000 1.53 392,000 305,000
1.0 ---------------------------------------------------------
M l 27,630,000 1.56 1,387,000 363,000
Inferred 6,560,000 1.47 310,000 (100,000)
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The mineral resource estimate has been calculated using the Canadian
Institute of Mining, Metallurgy and Petroleum ('CIM') Definitions Standards
for mineral resources in accordance with National Instrument 43-101 -
Standards of Disclosure for Mineral Projects.
Mineral resources which are not mineral reserves do not have demonstrated
economic viability.
Mineral resource update effective date: May 31, 2011.
(i) Rounded to nearest 10 thousand
(ii) Rounded to nearest 1 thousand. The July 2010 resources were released
without In-Pit simulation.
The in-pit mineral resource estimates were calculated based on the following geological and resource modeling parameters:
-- The mineral resources of the Hosco deposit have been estimated with two
distinct mining scenarios: open-pit and underground mining perspectives.
The open pit mineral resources are reported within a Whittle pit shell
optimised with the parameters used in the project's Pre-Feasibility
Study.
-- Mineral resources were evaluated using recent and historical data which
include 734 recent and 109 historical surface drill holes for a total
194,065 metres of surface drilling with an additional 3,243 historical
underground drill holes and channel samples. A total of 122,601 assays
are now available in the data bank.
-- The mineral resources were modeled and estimated using the software
SectCad v. 5.5.25.
-- The interpolation was conducted on composite assays of 2 metres in
length.
-- Capping of 15 grams of gold per tonne was applied to the assay
composites. Results are presented as undiluted and in-situ.
-- The mineral resource model was interpreted from transverse sections
ranging between 25 to 50 metres.
-- The interpolation was done by Ordinary Kriging in two stages: One block
model using mineralised envelopes for the high grade mineralisation
(greater than 0.5 grams of gold per tonne), and one block model for the
lower grade mineralisation located outside the defined mineralised
envelopes.
-- The block model was defined by a block size of 8 metres long by 5 metres
wide by 8 metres thick and covers a strike length of 3,000 metres to a
maximum depth of 1,000 metres below surface.
-- An average drill spacing of 25 metres x 25 metres is used in the
measured and indicated categories resources.
-- The average relative density used to calculate the tonnage for Hosco
deposit from the volumetric estimate of the resource block model has
been updated to 2.75t/m3, following an in-depth review of the specific
gravity of the mineralised lithologies observed at Hosco. The relative
density used for the previous resource estimates was 2.66t/m3.
-- Historical Hosco production of 9,704 oz has not been removed from
mineral resources.
Whittle
A Whittle pit optimisation was performed by SGS Geostat using the cost parameters from the Pre-Feasibility Study adjusted for a gold price of US$1,000 per ounce and an exchange rate of 1:1. The parameters are subject to revision upon completion of the detailed cost studies currently in progress. The base case pit simulation was performed with a minimum cut off grade of 0.33 grams of gold per tonne (base case). The results at a cut-off grade of 0.5 and 1.0 grams of gold per tonne are derived from the base case pit simulation.
The previous mineral resource estimates were not released as an in-pit resource using a whittle pit optimisation. In order to compare the May 2011 mineral resources to the July 2010 mineral resources, SGS Geostat performed a whittle pit simulation on the latter using the same parameters as of May 2011. The following table shows the results of this optimisation compared to the global resources released previously.
Table 2: Whittle pit optimisation July 2010 compared to global resources
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July 2010 (whittle July, 2010 (global without
simulation) wittle)
----------------------------------------------------
Grade
Cut-off Category Tonnes Grade Gold Tonnes Grade Gold
(Au g/t) In-Pit (t) (g/t) (oz) (t) (g/t) (oz)
----------------------------------------------------------------------------
Measured 26,750,000 1.38 1,186,000 26,780,000 1.38 1,187,000
Indicated 13,050,000 1.25 523,000 13,770,000 1.23 546,000
0.5 ---------------------------------------------------------------
M l 39,810,000 1.33 1,708,000 40,550,000 1.33 1,732,000
Inferred 9,200,000 1.29 381,000 23,170,000 1.19 887,000
----------------------------------------------------------------------------
The mineral resources located below the Hosco optimised pit shell were evaluated using an underground ('U/G') mining scenario. The base case cut-off grade for the U/G mineral resources at Hosco has been set at 2.0 grams of gold per tonne. The U/G mineral resources are reported in the Joanna Project mineral resources table below.
Geology
Mineralization at Joanna is closely related to the east-west Cadillac fault and forms a 200 metre wide corridor composed of different mineralized lenses parallel to the fault, dipping 55 degrees to the north. Mineralization takes the form of a few millimetres to a 15 centimetre-wide quartz vein network inside the altered sediment rock with finely-disseminated sulphides. Mineralization has been defined and correlated based on altered mineral assemblages (biotite, tremolite, carbonates, muscovite, tourmaline, chlorite), quartz textures, deformation features and sulphides types (pyrrhotite and arsenopyrite).
At Hosco, mineralization is located within three main lenses, one located north of the fault and two at the southern side of the fault. Each lens shows a thickness of between 15 and 60 metres and a variable lateral extension of between 300 and 700 metres.
Joanna Project Mineral Resources
The Joanna Project is 100% owned by Aurizon and comprised of five sectors based on different royalty owners. The Hosco sector currently represents the core of the mineral resources located on the property. The other sectors include Heva, Alexandria, Henriksen, and Aurizon. The project comprises 156 claims covering 4,294 hectares in 3 separate blocks.
As the updated resource outline of the Hosco deposit crosses over the Alexandria claim boundary, all the resources of the Alexandria sector have been revised. Similarly to Hosco, the average relative density for the Alexandria deposit has been changed to 2.75 t/m3.
The Heva resources on the Joanna property outside of the Hosco sector have not been updated and the mineral resource estimate figures remain the same as previously reported, with a relative density factor at 2.81 t/m3. In the previous release of Heva resources, a minimum cut-off at 0.5 grams of gold per tonne was used. In this news release, a minimum cut-off of 0.5 grams of gold per tonne for the resources from surface to a depth of 300 metres and 2.0 grams of gold per tonne for the resources below 300 metres were utilized.
The following table provides the details of the total mineral resources for the Joanna Project, including the May 2011 updated Hosco mineral resources:
Table 3: Joanna Updated Mineral Resources
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May 2011
------------------------------------------------
Cut-off
Mineral Resource grade Grade Gold
Resources Sectors Depth (g/t) Tonnes (g/t) (oz)
---------------------------------------------------------------------
Hosco In pit 0.5 28,840,000 1.37 1,275,000
Measured Heva Above 0.5 0 0.00 0
Alexan- 4,700m
dria Elev 0.5 0 0.00 0
---------------------------------------------------------------------
Total 28,840,000 1.37 1,275,000
---------------------------------------------------------------------
Hosco In pit 0.5 25,300,000 1.19 970,000
Hosco Underground 2.0 60,000 2.52 5,000
Indicated Heva Above 0.5 4,410,000 1.90 270,000
Alexan- 4,700m
dria Elev. 0.5 0 0.00 0
---------------------------------------------------------------------
Total 29,770,000 1.30 1,245,000
---------------------------------------------------------------------
Hosco In pit 0.5 54,140,000 1.29 2,245,000
Hosco Underground 2.0 60,000 2.52 5,000
Measured & Heva Above 0.5 4,410,000 1.90 270,000
Indicated Alexan- 4,700m
dria Elev. 0.5 0 0.00 0
---------------------------------------------------------------------
Total 58,610,000 1.34 2,520,000
---------------------------------------------------------------------
Hosco In pit 0.5 7,670,000 1.15 284,000
Hosco Underground 2.0 350,000 2.26 25,000
Heva Above 4,700m 0.5 7,680,000 1.70 421,000
Inferred Heva Elev. 2.0 650,000 2.80 59,000
Alexan- Underground
dria Above 4,700m 0.5 980,000 1.20 37,000
Elev.
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Total 17,330,000 1.48 826,000
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----------------------------------------------------------------------------
July 2010
-------------------------------------------------------
Cut-off Gain/
Mineral Resource grade Grade Gold Loss
Resources Sectors Depth (g/t) Tonnes (g/t) (oz) (oz)
----------------------------------------------------------------------------
Hosco In pit 0.5 26,750,000 1.38 1,186,000 89,000
Heva Above 0.5 0 0.00 0 0
Measured Alexan- 4,700m
dria Elev. 0.5 0 0.00 0 0
----------------------------------------------------------------------------
Total 26,750,000 1.38 1,186,000 89,000
----------------------------------------------------------------------------
Hosco In pit 0.5 13,050,000 1.25 523,000 447,000
Hosco Underground 2.0 20,000 2.65 2,000 3,000
Indicated Heva Above 0.5 4,410,000 1.90 270,000 0
Alexan- 4,700m
dria Elev. 0.5 0 0.00 0.00 0
----------------------------------------------------------------------------
Total 17,480,000 1.41 795,000 450,000
----------------------------------------------------------------------------
Hosco In pit 0.5 39,810,000 1.33 1,708,000 537,000
Measured & Hosco Underground 2.0 20,000 2.65 2,000 3,000
Indicated Heva Above 0.5 4,410,000 1.90 270,000 0
Alexan- 4,700m
dria Elev. 0.5 0 0.00 0.00 0
----------------------------------------------------------------------------
Total 44,240,000 1.39 1,980,000 540,000
----------------------------------------------------------------------------
Hosco In pit 0.5 9,200,000 1.29 381,000 (97,000)
Hosco Underground 2.0 440,000 2.55 36,000 (11,000)
Heva Above 4,700m 0.5 7,680,000 1.70 421,000 0
Inferred Heva Elev. 2.0 650,000 2.83 59,000 0
Alexan- Underground
dria Above 4,700m 0.5 1,100,000 1.20 42,000 (5,000)
Elev.
----------------------------------------------------------------------------
Total 19,070,000 1.53 939,000 (113,000)
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(i) Rounded to nearest 10 thousand - (ii) Rounded to nearest 1 thousand
Effective date: May 31, 2011
CIM definitions were followed for mineral resources
Mineral resources which are not mineral reserves do not have demonstrated
economic viability
Historical production of 9,794 oz (Hosco) and 10,700 oz (Heva) has not been
removed from mineral resources
Pre-Feasibility Study
The Pre-Feasibility Study was based on a mineral resource estimate from SGS Geostat dated November 2009. The in-situ mineral reserve estimate for the Hosco deposit as defined by the Pre-Feasibility Study was 23.6 million tonnes at 1.31 grams of gold per tonne equivalent to 995,600 ounces. The information contained in the Pre-Feasibility Study is currently being updated in the context of a Feasibility Study planned to be released during the third quarter 2011.
Outlook
The objective of the 2011 drill campaign is to perform step-out drilling on 50 metre spacing along the 2.5 kilometre strike length of the Heva deposit and potential satellite zones, down to 150 metres, in order to extend the mineral resources contour and to increase the quality of the existing indicated and inferred mineral resources. An initial $3.7 million exploration program, comprising 26,000 metres of surface drilling, concentrated on the Heva deposit, approximately 3 kilometres west of the proposed Hosco pit. Two to three drill rigs were active during the first five months of 2011. Assay results are pending from this program.
The Feasibility Study currently in progress will incorporate this updated resource estimate on the Hosco deposit of the Joanna property as well as the results from the metallurgical pilot tests, geotechnical study, updated capital cost and operating cost estimates, and other studies currently in progress or already complete. The Feasibility Study is expected to be completed during the third quarter, 2011. The environmental impact study has already been initiated and the report is expected to be completed by the end of 2011.
Qualified Person and Quality Control
Information of a scientific or technical nature in this news release has been prepared by or under the supervision of Ghislain Fournier P. Eng., Technical Services General Manager. The current mineral resource estimate was completed by Andre Laferriere, M.Sc. P.Geo, from SGS Canada Inc. (Geostat), an independent Qualified Person under NI 43-101 guidelines using the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Standards on Mineral Resources and Reserves, Definitions and Guidelines prepared by the CIM Standing Committee on Reserve Definitions and adopted by the CIM Council on December 11, 2005. The Pre-Feasibility Study contains details of Aurizon's data verification, QA and QC procedures and programs.
Additional Information
Additional information required by part 3 of NI 43-101 and not otherwise contained in this release can be found in the Pre-Feasibility Study for the Hosco Deposit dated December 22, 2009 and in the Mineral Resource Estimation - Joanna Gold Deposit, August 2010 Update, dated August 17, 2010, both of which are available under the company's profile at www.sedar.com.
A sketch is attached showing the updated resource outline for the Hosco Deposit at the Joanna Gold Project. All other information previously released on Joanna is also available on Aurizon's website at www.aurizon.com.
About Aurizon
Aurizon is a gold producer with a growth strategy focused on developing its existing projects in the Abitibi region of north-western Quebec, one of the world's most favourable mining jurisdictions and prolific gold and base metal regions, and by increasing its asset base through accretive transactions. Aurizon shares trade on the Toronto Stock Exchange under the symbol 'ARZ' and on the NYSE Amex under the symbol 'AZK'. Additional information on Aurizon and its properties is available on Aurizon's website at http://www.aurizon.com.
Forward Looking Statements and Information
This news release contains 'forward-looking statements' and 'forward-looking information' within the meaning of applicable securities regulations in Canada and the United States (collectively, 'forward-looking information'). The forward-looking information contained in this news release is made as of the date of this news release. Except as required under applicable securities legislation, the Company does not intend, and does not assume any obligation, to update this forward-looking information. Forward-looking information includes, but is not limited to, statements with respect to estimated mineral resources, anticipated effect of the completed drill results on the Joanna project, timing of a feasibility study, and timing and expectations of future work programs. Often, but not always, forward-looking information can be identified by the use of words such as 'plans', 'expects, 'is expected', 'budget', 'scheduled', 'estimates', forecasts', 'intends', 'anticipates', or 'believes', or the negatives thereof or variations of such words and phrases or statements that certain actions, events or results 'may', 'could', 'would', 'might', or 'will' be taken, occur or be achieved.
The forward-looking information contained in this news release is based on certain assumptions that the Company believes are reasonable, including, with respect to mineral resource estimates, the key assumptions and parameters on which such estimates are based, as set out in this news release and the technical report for the property, that the current price of and demand for gold will be sustained or will improve, the supply of gold will remain stable, that the general business and economic conditions will not change in a material adverse manner, that financing will be available if and when needed on reasonable terms and that the Company will not experience any material accident, labor dispute, or failure of plant or equipment.
However, forward-looking information involves known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of the Company to be materially different from any future results, performance or achievements expressed or implied by the forward-looking information. Such factors include, among others, conclusions of economic evaluations, the risk that actual results of exploration activities will be different than anticipated, that cost of labour, equipment or materials will increase more than expected, that the future price of gold will decline, that the Canadian dollar will strengthen against the U.S. dollar, that mineral resources and reserves are not as estimated, that actual costs or actual results of reclamation activities are greater than expected; that changes in project parameters as plans continue to be refined may result in increased costs, of unexpected variations in mineral resources and reserves, grade or recovery rates, of failure of plant, equipment or processes to operate as anticipated, of accidents, labour disputes and other risks generally associated with mining, unanticipated delays in obtaining governmental approvals or financing or in the completion of development or construction activities, as well as those factors and other risks more fully described in Aurizon's Annual Information Form filed with the securities commission of all of the provinces and territories of Canada and in Aurizon's Annual Report on Form 40-F filed with the United States Securities and Exchange Commission, which are available on the Company's website at www.aurizon.com and on Sedar at www.sedar.com and on Edgar at www.sec.gov/. Although the Company has attempted to identify important factors that could cause actual actions, events or results to differ materially from those described in forward-looking information, there may be other factors that cause actions, events or results to not be as anticipated, estimated or intended. There can be no assurance that forward-looking information will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Readers are cautioned not to place undue reliance on forward-looking information due to the inherent uncertainty thereof.
CAUTIONARY NOTE TO US READERS
As a Canadian reporting issuer, the Company is subject to rules, policies and regulations issued by Canadian regulatory authorities and is required to provide detailed information regarding its properties including mineralization, drilling, sampling and analysis, security of samples and mineral resource and mineral reserve estimates. In addition, as a Canadian reporting issuer, the Company is required to describe mineral resources associated with its properties utilizing Canadian Institute of Mining, Metallurgy and Petroleum ('CIM') definitions of 'indicated' or 'inferred', which categories of resources are recognized by Canadian regulations but are not recognized by the United States Securities and Exchange Commission ('SEC').
The SEC allows mining companies, in their filings with the SEC to disclose only those mineral deposits they can economically and legally extract or produce. Accordingly, information contained in this News Release regarding our mineral deposits may not be comparable to similar information made public by U.S. companies subject to the reporting and disclosure requirements under the United States federal securities laws and the rules and regulations of the Commission thereunder.
In particular, this News Release uses the term 'indicated' resources. U.S. readers are cautioned that while that term is recognized and required by Canadian regulations, the SEC does not recognize it. U.S. investors are cautioned not to assume that any part or all of mineral deposits in this category will ever be converted into mineral reserves.
This News Release also uses the term 'inferred' resources. U.S readers are cautioned that while this term is recognized and required by Canadian regulations, the SEC does not recognize it. 'Inferred resources' have a great amount of uncertainty as to their existence, and great uncertainty as to their economic and legal feasibility. It cannot be assumed that all or any part of an inferred mineral resource will ever be upgraded to a higher category. Under Canadian rules, estimates of inferred mineral resources may not form the basis of feasibility or pre-feasibility studies, except in rare cases. U.S. readers are cautioned not to assume that part or all of an inferred resource exists, or is economically or legally mineable.
U.S. Registration: (File 001-31893)
News Release: Issue No. 14 - 2011
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Contacts:
Aurizon Mines Ltd.
David P. Hall
President & CEO
604-687-6600
Aurizon Mines Ltd.
Martin Bergeron
VP Operations
819-874-4511
Aurizon Mines Ltd.
Jennifer North
Investor Relations
604-687-6600 or Toll Free: 1-800-411-GOLD (4653)
info@aurizon.com
www.aurizon.com
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(514) 939-3989
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Renmark Financial Communications Inc.
Maurice Dagenais
(514) 939-3989
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Renmark Financial Communications Inc.
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