Çöpler Resource estimate increases by 27% or 2.2 million ounces
TORONTO, Sept. 10, 2012 /CNW/ - Alacer Gold Corp. ("Alacer Gold" or the "Corporation") [TSX: ASR and ASX: AQG] today announces an updated Mineral Resource estimate for the Çöpler gold-silver-copper deposit in Turkey. The significant growth potential of Çöpler has been confirmed by a total of 2.2 million gold ounces (Measured, Indicated + Inferred Resources) being added in the past six months. This updated Mineral Resource will be used to update the Çöpler Mineral Reserve estimate in conjunction with the Çöpler Sulfide Feasibility Study which is planned to be completed in late 2012.
The updated Çöpler resource estimate has resulted in Measured and Indicated ("M+I") Resources increasing to 182.6 million tonnes at a grade of 1.4 grams per tonne ("g/t") gold, containing a total of 8.0 million ounces (inclusive of reserves) as at June 30, 2012. This represents a 900,000 ounce (11%) increase on the contained ounces in the previous M+I Resource, prior to mining depletion of approximately 176,000 ounces between December 31, 2011 and June 30, 2012.
|Mineral Resource for the Çöpler Deposit (100%) as at June 30, 2012|
|Mineralization Type||Resource Category||Tonnes (million)||Gold Grade (g/t)||Contained Gold (million ounces)||Silver Grade (g/t)||Copper Grade (%)||Sulfur Grade (%)|
|Measured + Indicated||53.8||1.2||2.0||2.3||0.1||0.3|
|Measured + Indicated||116.4||1.6||5.9||4.6||0.1||4.1|
|Measured + Indicated||182.6||1.4||8.0||3.9||0.1||2.9|
Note: Resources are quoted after mining depletion and are inclusive of reserves. Resources are shown on a 100% basis, of which Alacer Gold owns 80%. Resource methodology is summarised in the Technical Procedural Section of this announcement. Stockpiles consist of a ROM stockpile of 38kt at 3.6g/t and a leach pad stockpile estimated at 12.4Mt at 0.18g/t of recoverable gold as of 30 June, 2012. Silver, copper and sulfur grades are not included for stockpiles. Rounding errors will occur.
Mr. David Quinlivan, President and CEO of Alacer Gold, stated "Drilling over the past two years has enabled our exploration team to quickly add nearly four million ounces of gold to the Çöpler resource. This new resource estimate confirms that the Çöpler deposit contained more than 10 million ounces of gold prior to mining commencing in late 2010. The conservative nature of this new resource estimate is evidenced by the 18% positive reconciliation in ounces mined since operations began at Çöpler. In addition, the deposit remains open in most directions and several near-surface, well mineralized areas such as the old Çöpler village area are not yet fully included in the resource. A further 10 kilometers of drilling has been completed since the June resource cut-off date with eight drill rigs continuing on site."
This new resource is reported as at June 30, 2012 and includes mining depletion and drilling assay results received since the previous resource that was reported as at December 31, 2011 (released February 27, 2012).
A total of 2.2 million ounces of new Resources (Measured, Indicated and Inferred) have been added in the past six months and this growth trend can be seen in Figure 1 below.
The increase in contained ounces in the updated Mineral Resource estimate is the result of:
- Data from additional infill and extensional drilling completed between September 1, 2011 and June 30, 2012; and
- Further drilling and mining of the Manganese, Main and Marble Pits enabling a better understanding of the controls to gold mineralization.
Çöpler Mineral Resources Comparison
A pre-mining comparison of the previous Çöpler Mineral Resource estimate (released February 27, 2012) with the new Çöpler Mineral Resource estimate is provided in the table below. The comparison shows that the total M+I Resource has increased by 0.9 million ounces or 11% for contained gold. Including Inferred Resources, the total increase is 2.2 million ounces or a 27% increase in contained gold.
|Çöpler - Mineral Resources Comparison (100% ownership basis)|
|Previous Resource* Pre-mining||New Resource Pre-mining||Change|
|Measured + Indicated||48.9||1.6||2.5||63.0||1.2||2.5||29%||-22%||0%|
|Measured + Indicated||98.3||1.6||5.2||117.3||1.6||6.0||19%||-2%||17%|
|Measured + Indicated||147.2||1.6||7.6||180.4||1.5||8.5||23%||-9%||11%|
Notes: * The previous Mineral Resource estimate was announced by Alacer Gold on February 27, 2012. Resources are quoted before mining depletion and are inclusive of reserves. Cut-off grades for the previous resource are >= 0.3g/t gold for oxide and >= 0.6g/t gold for sulfide and for the new resource are >= 0.3g/t gold for oxide and >= 0.8g/t gold for sulfide.
Grade-tonnage curves for the Çöpler Mineral Resource in the "Technical Procedural Information" section of this announcement show how the resource varies with assumed cut-off grades. The new resource estimate is reported at a sulfide cut-off grade of 0.8g/t gold, compared with the 0.6g/t gold cut-off grade used for sulfide mineralization in the previous resource estimates. By way of comparison, the total new Measured and Indicated Resource (inclusive of reserves) reported at a 0.8g/t gold cut-off grade for sulfide is 116.4 million tonnes at 1.6g/t gold for 5.9 million ounces compared to 155.2 million tonnes at 1.4g/t gold for 6.8 million ounces at a 0.6g/t cut-off grade.
|Sulfide Mineral Resource for the Çöpler Deposit (100%) as at June 30, 2012|
|Sulfide Cut-Off Grade 0.8g/t||Sulfide Cut-Off Grade 0.6g/t|
|Resource Category||Tonnes (million)||Gold Grade (g/t)||Contained Gold (million ounces)||Tonnes (million)||Gold Grade (g/t)||Contained Gold (million ounces)|
|Measured + Indicated||116.4||1.6||5.9||155.2||1.4||6.8|
Note: Comparison of the June 30, 2012 Sulfide Resource at 0.6g/t gold and 0.8g/t gold cut-off grades. Resources are quoted after mining depletion and are inclusive of reserves.
For the volume mined up until June 30, 2012, this new resource model estimates 508,000 ounces of contained gold versus estimated mine production of 599,000 ounces of contained gold. This indicates that the new resource model is under-estimating the gold contained in the mined part of the Çöpler deposit with 18% more gold mined to June 30, 2012 than estimated by the new resource model.
The scale and complexity of the Main Zone mineralization has not allowed high-grade areas to be domained in detail. The resource model is considered likely to include more tonnes at a lower gold grade than that expected to be mined. Infill grade control drilling will enable mineralized zones to be better defined than is possible with the current drilling density.
Resources in the Inferred category have increased substantially due to areas of gold mineralization being intersected in deeper drilling at relatively wide spacing. This deeper drilling confirms geological continuity but the spacing is not sufficient to estimate the grade with greater confidence for a higher classification.
An overview of the distribution of gold mineralization contained in the new resource model is provided in the long section below in Figure 2. In addition, Figure 3 below provides an overview of the typical resource classification on cross section across the new resource model in Main Zone.
In addition to the potential upside in the resource estimate, significant upside exists to grow the Çöpler resource with 8 drill rigs remaining on site. Drilling is continuing to test for resource extensions to the north within the old Çöpler village area and resource extensions at depth between the Manganese Zone and Main Zone.
About Alacer Gold
Alacer Gold Corp. is a leading intermediate gold mining company with interests in multiple mines which provide ore to three processing facilities in Australia and Turkey:
- 80% interest in the Çöpler Gold Mine;
- 100% interest in the Higginsville Gold Operations;
- 100% interest in the South Kalgoorlie Gold Operations; and
- 49% interest in the Frog's Leg Gold Mine.
Alacer Gold's operations produced a total of 421,204 ounces of gold during 2011.
Alacer Gold is executing a growth strategy through the use of cash flows to grow production and cash margins to generate strong capital returns. While the primary objective is organic growth, the Corporation also identifies and evaluates strategic transactions that will add shareholder value.
The information in this report which relates to Mineral Resources is based on information prepared by Lisa Bascombe, a full-time employee of Alacer and a Member of the Australian Institute of Geoscientists.
The information in this report which relates to Mineral Resources has been reviewed by Chris Newman, a full-time employee of Alacer, who is a Member of the Australasian Institute of Mining and Metallurgy and a Member of the Australian Institute of Geoscientists.
Ms Bascombe and Mr Newman have sufficient experience which is relevant to the style of mineralization and type of deposit under consideration and to the activity which is being undertaken to qualify as a Competent Person as defined in the 2004 Edition of the "Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves" and a qualified person pursuant to National Instrument 43-101 of the Canadian Securities Administrators. Ms Bascombe and Mr Newman consent to the inclusion in this release of the matters based on this information in the form and context in which it appears.
Technical Procedural Information
Çöpler Resource Estimation Methodology
Current Mineral Resource estimates are stated as at June 30, 2012 and take account of mining depletion to that date. Resources are shown on a 100% basis, of which Alacer Gold owns 80%. All resource numbers quoted in this announcement are reported inclusive of reserves.
Drillhole data used in the Çöpler resource was comprised of surface reverse circulation ("RC") and surface diamond drillholes. The majority of drillhole collar locations were surveyed by contract mine surveyors. Drillholes were routinely downhole surveyed using Eastman single-shot and Reflex multi-shot cameras. Drillhole spacing varies across the deposit, with the majority of the resource drilled at 40m x 40m spacing, however infill drilling has been completed down to 20m x 20m in the Manganese and Marble Zones of the resource.
Drill core and RC chips were logged in detail for lithology, alteration, mineralization, structure and veining. All data is stored and validated within an electronic database. Following logging, the samples are submitted for assaying. Drill core is sawn in half and sampled (or split into half core for clay ores); whereas RC chip samples are routinely collected in calico bags at 1m increments for assay. Sample lengths were constrained by geology, alteration, mineralization or structural boundaries and may vary in different areas of the resource. The samples range in downhole lengths from 0.2m to 4.6m.
Gold analyses were undertaken by ALS-Chemex in Vancouver, BC, Canada using a 30g Fire Assay analysis method. Multi-element analyses of silver, copper and sulfur were undertaken by four acid digestion ICP-AES. Industry standard reference materials and blanks were utilized in order to check laboratory assay quality control. A laboratory visit and audit was undertaken in June 2012.
Detailed geological and mineralization wire-frames have been built utilizing data collected during the logging of drillholes in the resource area. Surface mapping and pit mapping collected from within the Manganese Pit have been integrated into the geological wireframes. A total of 39 mineralization domains have been defined for the resource estimate, with 13% of ounces in the resource estimate outside of these domains.
Assays were composited to 3m intervals and assessed for appropriate top-cuts by area. The top-cuts applied to each element by area are detailed in the table below.
|Area||Au g/t||Ag g/t||Cu%||Mn%||As%|
|Main Zone East||10||20||0.80||0.90||1.00|
|Main Zone West||3||10||0.90||0.60||0.21|
A detailed review of 2,409 bulk density measurements collected from diamond drillholes within the resource area has identified the presence of surficial weathering within several of the rock types. This results in a reduction of the bulk density of diorite and metasediments with proximity to the surface. The bulk densities utilized within the resource are detailed in the table below.
|Geology||Vertical depth from surface||Bulk Density|
|Diorite||0 to 20||2.20|
|Diorite||20 to 40||2.36|
|Diorite||40 to 60||2.48|
|Metasediments||0 to 20||2.37|
|Metasediments||20 to 40||2.48|
|Metasediments||40 to 60||2.55|
The grade estimation method utilized to estimate the Çöpler resource was Ordinary Kriging. Parent block sizes were set at 10m (X), 10m (Y) and 5m (Z) in the Manganese and Marble Zones of the resource, where drilling is closer spaced; whereas the parent block sizes in all other areas were set at 20m (X), 20m (Y) and 5m (Z). The minimum sub-block size was set to 2.5m (X), 2.5m (Y) and 2.5m (Z) in all areas.
A nominal cut-off grade of 0.3g/t gold was applied to the oxide portion of the resource and 0.8g/t gold to the sulfide portion of the resource to reflect likely mining and processing scenarios. The resource estimate has been classified based on data density, data quality, confidence in the geological interpretation and grade continuity, and the confidence in the estimation. The resource has been reported prior to any recovery factors.
The major differences between the previous resource (released February 27, 2012) and this resource are detailed below.
- A reduction in the block sizes used in the resource model from 15m (X) 15m (Y) 10m (Z) to 10m (X) 10m (Y) 5m (Z) in the Manganese and Marble areas; and from 30m (X) 30m (Y) and 10m (Z) to 20m (X) 20m (Y) 5m (Z) in all other areas.
- Drillholes were composited to 3m intervals due to the significant increase in data density. A detailed analysis of the impact of compositing to a 3m length was undertaken on the data prior to the estimation being run and identified no material impact on the grade of the composites available for estimation.
- The minimum and maximum numbers of samples used to estimate the resource were reduced to four and 12 respectively, in order to reflect the change in composite length.
- The 3m composites were imported into the variography files from the previous model. Minor decreases in the nugget effect were evident in less than 50% of the ore domains, a function of the increased composite length. The variography in the remaining domains changed a minor amount.
- The Main Zone was wire-framed with an epithermal dome geometry which was unfolded in Vulcan 8.1.3 using the tetra modeling function, enabling the estimation of the dome as a whole.
- Sulfur was estimated separately from the other elements using an Indicator Kriging method. An indicator of 3% sulfur was selected and blocks with a likelihood of 35% or higher being equal to or above the 3% sulfur indicator were selected for estimation in a high-grade sulfur domain. Wire-frames of the high-grade sulfur domain were generated and blocks and samples coded for use in the resource estimation. A variographic analysis of the high-grade and low-grade sulfur domains was undertaken and the sulfur domains estimated using Ordinary Kriging.
- The topographic surface used for the estimation was produced using 5m contours, rather than the previous topographic surface, which was produced from 10m contours.
- Arsenic and manganese were estimated for metallurgical characterization purposes.
- The reported cut-off grade was increased from 0.6g/t to 0.8g/t for sulfide ore.
The graphs below provide grade-tonnage curves for oxide and sulfide M+I Resources at various cut-off grades.
Certain statements contained in this news release constitute forward-looking information, future oriented financial information, or financial outlooks (collectively "forward-looking information") within the meaning of Canadian securities laws. Forward-looking information may relate to this news release and other matters identified in Alacer's public filings, Alacer's future outlook and anticipated events or results and, in some cases, can be identified by terminology such as "may", "will", "could", "should", "expect", "plan", "anticipate", "believe", "intend", "estimate", "forecast", "projects", "predict", "potential", "continue" or other similar expressions concerning matters that are not historical facts and include, but are not limited in any manner to, those with respect to proposed exploration, communications with local stakeholders and community relations, status of negotiations of joint ventures, commodity prices, mineral resources, mineral reserves, realization of mineral reserves, existence or realization of mineral resource estimates, the timing and amount of future production, timing of studies and analysis, the timing of construction of proposed mines and process facilities, capital and operating expenditures, economic conditions, availability of sufficient financing, exploration plans and any and all other timing, exploration, development, operational, production, financial, economic, legal, social, regulatory and, political factors that may influence, or be influenced by, future events or conditions. Such forward-looking statements are based on a number of material factors and assumptions, including, but not limited in any manner, those disclosed in any other Alacer filings, and include exploration results and the ability to explore, the ultimate determination of mineral reserves, availability and final receipt of required approvals, titles, licenses and permits, sufficient working capital to develop and operate the mines, access to adequate services and supplies, commodity prices, ability to meet production targets, foreign currency exchange rates, interest rates, access to capital markets and associated cost of funds, availability of a qualified work force, ability to negotiate, finalize and execute relevant agreements, lack of social opposition to the mines, lack of legal challenges with respect to any the property or the Company and the ultimate ability to mine, process and sell mineral products on economically favourable terms. While we consider these assumptions to be reasonable based on information currently available to us, they may prove to be incorrect. Actual results may vary from such forward-looking information for a variety of reasons, including but not limited to risks and uncertainties disclosed in other Alacer filings at www.sedar.com and other unforeseen events or circumstances. Other than as required by law, Alacer does not intend, and undertakes no obligation to update any forward-looking information to reflect, among other things, new information or future events.
SOURCE ALACER GOLD CORP.
More by this Source
Alacer announces President Howard Stevenson to resign
Jan 27, 2014, 07:55 ET
Alacer Gold announces a further 10% increase in 2013 production guidance at Çöpler
Dec 05, 2013, 07:45 ET
Browse our custom packages or build your own to meet your unique communications needs.
Learn about PR Newswire services
Request more information about PR Newswire products and services or call us at (888) 776-0942.