High River Gold Reports “Initial” NI 43-101 Resource Estimate for Prognoz Silver Project
High River Gold Mines Ltd. (“High River” or the “Company”) (TSX: HRG) is pleased to report the results of the “Initial” Canadian Institute of Mining, Metallurgy and Petroleum National Instrument 43-101 (“NI 43-101″) compliant silver resource estimate, completed by MICON International Limited (“MICON”), on the Prognoz Silver Project (“Prognoz”). The technical report contains resource estimates (indicated and inferred) for two veins (Glavnoye and Boloto) as well as an evaluation of the conceptual additional resource potential for 8 other veins and the Boloto strike extension.
This “Initial” resource estimate is based on drilling and trenching completed to the end of May 2007. An “Updated” Resource Estimate is planned for completion in Q2 2008 which will incorporate the results of drilling completed in 2007 since May (an additional 85 holes have been completed on the Glavnoye and Boloto veins to the end of November) and holes planned to be completed in early 2008.
– “Initial” NI 43-101 Resource Estimate:
— Indicated Resource: 71,500,000 ounces of silver
— Inferred Resource: 39,200,000 ounces of silver
These Resources are based largely on the Glavnoye vein, and to a lesser extent on the Boloto vein. The potential exists to increase these Resources as both veins remain open along strike in both directions and to depth.
– Estimate of Potential Additional Resources: 97,000,000 to 194,000,000 ounces of silver
This potential additional resource reflects the potential of 8 other known veins on the property (and additional potential at Boloto) which was not included in the Resource Estimate. The evaluation of the potential for these veins was based on the results of mineral samples obtained during trenching and preliminary exploration drilling.
In total, more than 30 silver veins have been identified on the Prognoz property and some may prove to be just as extensive as the Glavnoye and Boloto veins.
Background
During 2006, High River’s 85%-owned Russian subsidiary, OJSC Buryatzoloto, acquired a 50% interest in and operatorship of the Prognoz Silver Project, situated in the Republic of Sakha (Yakutia) of the Russian Federation. This 56 square kilometre property hosts over 30 epithermal veins which are on average 2 to 4 metres wide, several kilometres long, and several hundred metres deep.
Extensive drilling and trenching has been conducted on the Prognoz property. Historical work consisted of 89 diamond drill holes (17,805 metres) and 317 trenches (17,756 metres). During 2006 and 2007 to the end of November 2007, Buryatzoloto drilled a further 676 core holes (61,481 metres), of which 206 holes (32,913 metres) were on the Glavnoye and Boloto veins, and extracted a 17 tonne bulk sample for metallurgical testwork.
“Initial” NI 43-101 Resource Estimate ————————————————————————— Indicated Resources ————————————————————————— Tonnage (t) Silver grade (g/t) Contained Silver (oz) ————————————————————————— 3,500,000 636 71,500,000 ————————————————————————— ————————————————————————— Inferred Resources ————————————————————————— Tonnage (t) Silver grade (g/t) Contained Silver (oz) ————————————————————————— 2,210,000 551 39,200,000 —————————————————————————
The “Initial” 43-101 Resource Estimate was based on extensive drilling consisting of 198 diamond drill holes, comprised of 121 holes drilled by Buryatzoloto up to May 31, 2007 and 77 historical holes. The validity of the historical data has been confirmed by Buryatzoloto drilling. Due to limited assaying capabilities in Russia, a significant backlog in assay results occurred during 2007, resulting in the “Initial” 43-101 Resource Estimate only including drilling completed prior to May 31, 2007.
MICON stated that the resource estimate is not materially affected by any known environmental, permitting, legal, title, taxation, socio-economic, marketing, political or other relevant issues, and that there are no known mining, metallurgical, infrastructure, or other factors that materially affect this resource.
The Qualified Persons responsible for the calculation of this NI 43-101 Resource Estimate are William J. Lewis, B.Sc., P. Geo. (APEGB # 20333, APEGM #20480, NAPEGG #1450, APGO #1522), a senior geologist with MICON based in Toronto, Canada, and Dibya Kanti Mukhopadhyay (MAusIMM), a senior mineral resource geologist with MICON based in Norwich, England.
Diamond Drilling (Glavnoye and Boloto Veins) —————————————————– Glavnoye Vein Boloto Vein Total —————————————————– Holes Metres Holes Metres Holes Metres ————————————————————————— Historical 67 13,400 10 2,000 77 15,400 ————————————————————————— 2006 80 10,738 5 513 85 11,251 ————————————————————————— 2007 (Jan-May) 33 6,100 3 490 36 6,590 ————————————————————————— ————————————————————————— Basis for Resource Estimate 180 30,238 18 3,003 198 33,241 ————————————————————————— 2007 (June-Nov.) 48 9,034 37 6,038 85 15,072 ————————————————————————— ————————————————————————— Total Drilling To Date 228 39,272 55 9,041 283 48,313 —————————————————————————
Further Notes to the “Initial” NI 43-101 Resource Estimate:
1. The geologic model used a break-even, cut-off grade of 100 g/t Ag, calculated by MICON (see Appendix 1 for sensitivity of the resource to different cut-off grades).
2. Assay results were capped at grades ranging from 1,755 g/t to 7,149 g/t depending on the zones sampled. The average capping grade, weighted by number of samples, was 5,610 g/t. Only 1.7% of the samples were affected due to capping.
3. The block model grade interpolation was performed using ordinary kriging.
4. Mineral Resources were calculated following NI 43-101 and JORC guidelines. Indicated Resources were defined as that portion of mineralization drilled on 40 metre centres. Indicated Resource blocks were estimated based on a minimum of 3 samples. Inferred Resources were defined as that portion of mineralization defined by surface sampling and few drill hole samples. For Inferred Resources, the lower density of drill hole data does not provide enough confidence to predict grade continuity, only geologic continuity.
5. Mineral Resources that are not mineral reserves do not have demonstrated economic viability.
“Updated” NI 43-101 Resource Estimate
An “updated” NI 43-101 resource estimate is planned for completion in Q2 2008, and will reflect results from drilling conducted during the second half of 2007 and early 2008.
Estimate of Potential Additional Resources
In addition to the Glavnoye and Boloto veins, more than 30 silver veins in total have been identified on the Prognoz property. Limited drilling and trenching, including 52 core holes (7,290 metres), was completed on 8 other veins.
Diamond Drilling Other 8 Veins Prospecting Metallurgical Total Testing ————————————————————– Holes Metres Holes Metres Holes Metres Holes Metres ————————————————————————— Historical 5 1,000 7 1,400 12 2,400 ————————————————————————— 2006 2 249 29 1,448 12 358 43 2,055 ————————————————————————— 2007 (Jan-Nov.) 45 6,041 360 19,522 22 950 427 26,513 ————————————————————————— ————————————————————————— Total Drilling (Non-Resource Estimate) 52 7,290 396 22,370 34 1308 482 30,968 —————————————————————————
High River and MICON believe the potential to increase silver resources at Prognoz is substantial. As such, MICON has estimated the conceptual resource potential, which is not included in the Resource Estimate, for these 8 other veins and the Boloto strike extension:
———————————————————————– —- —————————————————————— ——— Mineral Mineral Average Potential Potential Potential Potential Silver Contained Contained Range (t) Grade (g/t) Silver (oz) Silver (t) ————————————————————————— Minus 20% 3,698,000 815 97,000,000 3,000 ————————————————————————— 4,622,232 815 121,221,865 3,770 ————————————————————————— Plus 60% 7,396,000 815 194,000,000 6,000 ————————————————————————— —————————————————————————
Since the mineral potential of a property cannot be estimated to the same accuracy as a mineral resource it must be stated as a range. To calculate a range, MICON applied a factor of minus 20% for the down side and plus 60% for the upside potential. The upside potential factor is larger than the downside potential factor because of the possibility that the mineralized zones will be similar in nature to, and as extensive as, the Glavnoye and Boloto zones. MICON also indicated that contributing to the upside potential is the possibility that additional veins related to existing veins could be discovered (off-splays and anastomosing vein branches).
It should be noted that the mineral potential of the Prognoz property is conceptual in nature and that there has been insufficient exploration conducted on the portions of the 8 veins and the Boloto strike extension, contained within the mineral potential evaluation, to define a mineral resource. It is also uncertain if further exploration will result in the targets being delineated as mineral resources.
Appendix 2 summarizes the data and parameters used to calculate the conceptual mineral potential of the portions of the 8 veins and the Boloto strike extension that have not been explored to the extent of the Glavnoye and Boloto zones contained within the NI 43-101 Resource Estimate.
In most cases where the depth of the mineralized zone is unknown, the depth of the mineralized zone has been estimated at 100 metres. This depth was used as it corresponds approximately to 1/3 of the depth of the known mineralization at the Glavnoye deposit. The depth of mineral potential for those zones which have been explored by drill holes has been set at 50 metres below the lowest mineralized drill intersection.
For the potential calculation, a mineral-bearing factor equalling 0.3 was used. The mineral-bearing factor is equal to the proportion of the mineralized zone which is mineral-bearing. A mineral-bearing factor value of 0.3 was selected as it was close to the average factor value calculated for the already explored Glavnoye and the Boloto deposits.
About High River
High River is a gold company with producing mines, mines under development, and advanced exploration projects in Burkina Faso and Russia. High River is bringing two new open-pit gold mines into production. The Taparko-Bouroum Gold Mine in Burkina Faso achieved commercial production in September 2007, and the Berezitovy Gold Mine in Russia is expected to achieve commercial production shortly. Gold production from Taparko-Bouroum for 2008 is planned at 100,000 ounces increasing to approximately 140,000 ounces in 2009 and the following years, and annual production from Berezitovy is expected to exceed 100,000 ounces. Combined with gold production from producing underground mines in Russia, Zun-Holba and Irokinda, High River’s attributable unhedged gold production is expected to exceed 300,000 ounces in 2008. In addition, the Company has two advanced exploration projects, the Bissa Gold Project in Burkina Faso and the world-class Prognoz Silver Project in Russia. These projects are expected to significantly add to the Company’s production profile in the future.
Forward Looking Statements – This press release contains forward-looking statements based on current expectations. These forward-looking statements entail various risks and uncertainties that could cause actual results to differ materially from those reflected. Risk and uncertainties about the Company’s business are more fully discussed in the Management’s Discussion and Analysis published in the Company’s Annual Report and in the Annual Information Form.
Appendix 1 Mineral Resource at Different Cut-offs ————————————————————————— Indicated Resources Inferred Resources —————————————————————- Silver Silver Cut-off Tonnes grade Ounces Tonnes grade Ounces (g/t) (millions) (g/t) (millions) (millions) (g/t) (millions) ————————————————————————— 0 4.04 554 72.0 2.37 517 39.4 ————————————————————————— 50 3.67 609 71.9 2.28 537 39.4 ————————————————————————— 100 3.50 636 71.5 2.21 551 39.2 ————————————————————————— 150 3.18 687 70.2 2.07 580 38.6 ————————————————————————— 200 2.83 749 68.2 1.80 642 37.1 ————————————————————————— Appendix 2 Summary of the Data and Parameters used for the Prognoz Property Additional Resource Potential Calculation ————————————————————————— Zone No. of No. of Strike Average Depth for Trench Drill Length Vein Potential Intersections Hole (m) Thickness Evaluation /No. of Intersections (m) (m) Channel /No. of Core Samples Samples ————————————————————————— ————————————————————————— Dalnaya 1,2 11/16 2/4 1,000 1.25 150 ————————————————————————— Krutaya 2/3 – 1,050 1.20 100 ————————————————————————— Solnechnaya 7/28 – 2,300 3.44 100 ————————————————————————— Osenn’aya 21/44 10/19 3,500 1.40 190 ————————————————————————— Yuznaya-3 6/8 3/6 3,900 1.02 130 ————————————————————————— Yuznaya-2 – 1/1 300 0.28 100 ————————————————————————— Yuznaya-1 4/8 2/7 1,050 1.64 130 ————————————————————————— Tikaya 14/28 1/4 5,600 1.52 100 ————————————————————————— Vesenn’aya-4 1/1 – 1,310 1.25 100 ————————————————————————— Vesenn’aya-3 3/3 3/5 1,800 0.67 160 ————————————————————————— Vesenn’aya-2 7/13 3/10 2,300 1.64 120 ————————————————————————— Vesenn’aya-1 1/1 1/1 2,100 0.16 100 ————————————————————————— Boloto-2 1/3 5/37 2,000 3.05 200 ————————————————————————— Udachnaya 3/3 – 1,000 0.60 100 ————————————————————————— Total 81/159 31/94 ————————————————————————— ————————————————————————— Zone Block Specific Mineral Mineral Average Potential Volume Gravity Bearing Potential Silver Contained (m3) (t/m3) Factor (t) Grade Silver (g/t) (oz) ————————————————————————— ————————————————————————— Dalnaya 1,2 375,462 3 0.3 337,915 386.0 4,193,653 ————————————————————————— Krutaya 126,000 3 0.3 113,400 198.8 724,815 ————————————————————————— Solnechnaya 791,857 3 0.3 712,671 198.8 4,555,155 ————————————————————————— Osenn’aya 932,125 3 0.3 838,913 1,049.1 28,296,422 ————————————————————————— Yuznaya-3 515,287 3 0.3 463,758 490.9 7,319,513 ————————————————————————— Yuznaya-2 8,485 3 0.3 7,637 581.0 142,658 ————————————————————————— Yuznaya-1 172,674 3 0.3 155,407 438.2 2,189,478 ————————————————————————— Tikaya 849,731 3 0.3 764,758 644.2 15,839,536 ————————————————————————— Vesenn’aya-4 163,750 3 0.3 147,375 1,032.4 4,891,809 ————————————————————————— Vesenn’aya-3 119,785 3 0.3 107,807 455.3 1,578,128 ————————————————————————— Vesenn’aya-2 377,444 3 0.3 339,700 560.7 6,123,840 ————————————————————————— Vesenn’aya-1 32,774 3 0.3 29,495 1,436.3 1,362,044 ————————————————————————— Boloto-2 610,439 3 0.3 549,395 2,358.8 41,665,207 ————————————————————————— Udachnaya 60,000 3 0.3 54,000 1,169.5 2,030,447 ————————————————————————— Total 4,622,232 815.6 120,912,708 —————————————————————————
Contacts: High River Gold Mines Ltd. Dan Hrushewsky Vice President, Investor Relations (416) 947-1440 (416) 360-0010 (FAX) Email: info@hrg.ca Website: www.hrg.ca
SOURCE: High River Gold Mines Ltd.