Riverstone Announces Significant Increase of Gold Mineralization at Karma Project
09.01.2012 | Marketwired
VANCOUVER, 01/09/12 -- Riverstone Resources Inc. (TSX VENTURE: RVS) (OTCQX: RVREF) (FRANKFURT: 3RV) announces an updated independent NI 43-101 compliant Mineral Resource estimate, that shows an increase of 42% for the global mineral inventory compared to the February, 2011 resource estimate at its flagship Karma gold project in Burkina Faso, West Africa (See RVS news release dated February 28, 2011). The NI 43-101 compliant resource estimate has been completed by P&E Mining Consultants Ltd. ('P&E') of Brampton, ON. The estimate was completed on the Goulagou I, Goulagou II, Kao, Rambo and Nami deposits which are all in close proximity to each other.HIGHLIGHTS (resources are contained within five Whittle open pit shells)
- Global Mineral Inventory (inside and outside of Whittle pit shells) consists of indicated gold mineralization totaling 1,773,000 ounces of gold in 54.1 Mt at an average grade of 1.02 g/t Au and inferred gold mineralization totaling 959,000 ounces of gold in 37.4 Mt at an average grade of 0.8 g/t Au.
- A significant portion of the gold resources are at shallows depth (less than 200 metres vertical depth) and over 80% of the global mineral inventory is contained with the five Whittle pit shells (see map: http://www.riverstoneresources.com/i/maps/120107-120105KarmaResLSect.jpg).
- Total Indicated gold resources within five Whittle pits are 1,634,000 ounces of gold in 47.34 Mt at an average grade of 1.07 g/t Au.
- Total Inferred gold resources within five Whittle pits are 566,000 ounces of gold in 18.93 Mt at an average grade of 0.93 g/t Au.
- 74% of the resources within the Whittle pit shells are classified as Indicated gold resources.
- Mineralization remains open at depth and along strike in at least one direction for all deposits.
- This resource will be used as the basis for proceeding with a Preliminary Economic Assessment (PEA) commencing in Q1, 2012.
'We are extremely pleased with the material increase of Indicated resources at Karma' commented Dwayne L. Melrose, President and COO of Riverstone Resources Inc. 'This will provide a solid base for going forward with engineering and economic studies in 2012 to establish Karma as one of the premier gold projects in West Africa. There is also significant potential to continue to increase the gold resource. We have completed 25,229 metres of drilling that are not included in the resource estimate and are presently drilling with five rigs'.
The Karma project consists of five separate deposits, which are located in close proximity to each other. A summary of the resource estimates within a Whittle pit shell for each deposit is presented in the table below:
KARMA IN PIT RESOURCE ESTIMATE(1)(2)(3)(4)(5)
(Within Whittle pit shells)(6)
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Cut Off Grade
Deposit Category Au g/t Type Tonnes (g/t) Au-oz
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GOULAGOU I Indicated 0.30 Oxide 4,345,079 0.682 95,274
0.36 Transition 1,567,103 0.715 36,024
0.40 Sulphide 6,494,450 0.833 173,931
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Subtotal 12,406,632 0.765 305,229
Inferred 0.30 Oxide 1,822,145 0.711 41,653
0.36 Transition 268,478 0.735 6,344
0.40 Sulphide 4,069,110 0.947 123,891
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Subtotal 6,159,733 0.868 171,888
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GOULAGOU II Indicated 0.30 Oxide 6,175,041 1.184 235,062
0.36 Transition 1,759,506 1.499 84,797
0.40 Sulphide 7,715,536 1.459 361,919
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Subtotal 15,650,083 1.355 681,778
Inferred 0.30 Oxide 486,873 0.558 8,735
0.36 Transition 151,398 0.682 3,320
0.40 Sulphide 1,306,676 1.308 54,950
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Subtotal 1,944,947 1.072 67,004
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KAO Indicated 0.30 Oxide 6,675,423 0.891 191,226
0.36 Transition 1,739,849 1.016 56,832
0.40 Sulphide 7,839,096 1.030 259,593
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Subtotal 16,254,368 0.971 507,651
Inferred 0.30 Oxide 2,503,639 0.801 64,475
0.36 Transition 384,970 0.850 10,520
0.40 Sulphide 7,375,503 0.984 233,333
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Subtotal 10,264,112 0.934 308,329
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NAMI Indicated 0.30 Oxide 563,848 1.064 19,288
0.36 Transition 715,888 0.908 20,899
0.40 Sulphide 995,465 1.043 33,381
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Subtotal 2,275,201 1.006 73,568
Inferred 0.30 Oxide 103,256 0.965 3,204
0.36 Transition 132,865 0.865 3,695
0.40 Sulphide 144,275 0.900 4,175
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Subtotal 380,396 0.905 11,073
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RAMBO Indicated 0.30 Oxide 188,275 2.306 13,959
0.36 Transition 244,970 2.997 23,604
0.40 Sulphide 321,964 2.732 28,280
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Subtotal 755,209 2.712 65,843
Inferred 0.30 Oxide 95,421 1.520 4,663
0.36 Transition 37,215 0.597 714
0.40 Sulphide 47,087 1.608 2,434
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Subtotal 179,723 1.352 7,812
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TOTAL Indicated 0.30 Oxide 17,947,666 0.961 554,808
0.36 Transition 6,027,316 1.146 222,157
0.40 Sulphide 23,366,511 1.141 857,105
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Total 47,341,493 1.074 1,634,069
TOTAL Inferred 0.30 Oxide 5,011,334 0.762 122,729
0.36 Transition 974,926 0.785 24,594
0.40 Sulphide 12,942,651 1.006 418,783
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Total 18,928,911 0.930 566,106
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(1) Resource estimates were based on a gold price of US$1250 per ounce, a
90%, 75% and 95% respective process recoveries for oxide, transition
and sulphide; ore mining costs of US$1.75/tonne, $US1.00 per tonne for
oxide and transition waste US$1.50 for sulphide waste ; process costs
of US$8/tonne for oxide and transition and US$12.50 per tonne for
sulphide; and General & Administrative costs of US$3 tonne were used
to determine the respective 0.30, 0.36 and 0.40 oxide, transition and
sulphide open pit cut-off grades.
(2) Au grades were estimated in a 5m x 5m x 5m block model (except Rambo
at 2.5m x 2.5m x 2.5m blocks) from capped 2.0m composites utilizing
inverse distance cubed interpolation. Composites were capped up to 45
g/t depending on the individual mineralized domain.
(3) Mineral resources which are not mineral reserves do not have
demonstrated economic viability. The estimate of mineral resources may
be materially affected by environmental, permitting, legal, title,
taxation, sociopolitical, marketing, or other relevant issues.
(4) The quantity and grade of reported Inferred resources in this
estimation are uncertain in nature and there has been insufficient
exploration to define these Inferred resources as an Indicated or
Measured mineral resource and it is uncertain if further exploration
will result in upgrading them to an Indicated or Measured mineral
resource category.
(5) The mineral resources in this press release were estimated using the
Canadian Institute of Mining, Metallurgy and Petroleum (CIM), CIM
Standards on Mineral Resources and Reserves, Definitions and
Guidelines prepared by the CIM Standing Committee on Reserve
Definitions and adopted by CIM Council.
(6) Material within Whittle pit shells have engineering mining aspects
applied to the global mineral inventory.
Riverstone Resources Inc. (TSX VENTURE: RVS) will be hosting a webcast and conference call subsequent to the release of the updated Karma Gold Project Resource Estimation. The call will be hosted by Dwayne Melrose, President, and Michael McInnis, CEO & Chairman of Riverstone Resources. Mr. Melrose and Mr. McInnis will be available to respond to questions following a brief presentation.
Conference Call Details: January 9, 2012
Conference Time: 2:00 pm Pacific Time
Participant Dial-in No. 416-340-2217 / 866-696-5910
Participant Pass Code: 3045426
An Operator will direct participants to the call.
Webcast Link: http://www.gowebcasting.com/3016
Instant Replay of the Call:
Dial-in numbers: 905-694-9451 / 800-408-3053
Pass Code: 1383245
Prompts: Full Name, Company Name
End Date: 23-Jan-2012 11:59PM
Riverstone maintains a quality control program involving the use of repeat assays, inserted blanks and the use of certified standards from an accredited Canadian laboratory. All core and reverse circulation samples are assayed using standard fire assay with atomic absorption techniques, with samples grading over one gram gold per tonne re-assayed with a gravimetric finish, at the independent Abilab Burkina SARL laboratories in Ouagadougou, Burkina Faso, which is part of the ALS Chemex group.
The resource estimation is based on a total of 815 diamond and reverse circulation drill holes for 104,881 metres. Subsequent to the February 2011 resource estimation, a total of 251 new diamond and reverse circulation holes for 41,224 metres are credited to the resource update. A total of 136 holes for 25,229 metres of drilling have been completed for which assays have not been received to date, and are not included into this resource update.
Riverstone will continue with the on-going drill program to further extend and upgrade the resource quality of the 5 deposits and also to test regional targets throughout 2012.
All reported resources fell within the limits of the mineralized wire frames. All interpolated grade blocks or partial blocks within the resource wire frames need to have at least three composites from two holes within 50 metres to be classified as Indicated Resource. Inferred Resources were determined from the remaining blocks, or partial blocks that lie within the wire frames.
KARMA GLOBAL MINERAL INVENTORY ESTIMATE
(within and outside of Whittle pit shells)
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Cut Off Grade
Deposit Category Au g/t Type Tonnes (g/t) Au-oz
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GOULAGOU I Indicated 0.30 Oxide 4,893,995 0.659 103,691
0.36 Transition 1,858,951 0.699 41,777
0.40 Sulphide 8,101,380 0.791 206,028
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Subtotal 14,854,326 0.736 351,495
Inferred 0.30 Oxide 2,279,964 0.662 48,526
0.36 Transition 494,454 0.652 10,365
0.40 Sulphide 11,830,163 0.736 279,936
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Subtotal 14,604,581 0.722 338,827
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GOULAGOU II Indicated 0.30 Oxide 6,343,699 1.169 238,423
0.36 Transition 1,821,215 1.468 85,956
0.40 Sulphide 8,811,914 1.379 390,683
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Subtotal 16,976,828 1.310 715,062
Inferred 0.30 Oxide 551,300 0.550 9,749
0.36 Transition 259,456 0.608 5,072
0.40 Sulphide 2,946,590 1.060 100,419
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Subtotal 3,757,346 0.954 115,239
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KAO Indicated 0.30 Oxide 7,138,693 0.865 198,529
0.36 Transition 1,948,584 0.975 61,082
0.40 Sulphide 9,151,657 0.973 286,288
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Subtotal 18,238,934 0.931 545,899
Inferred 0.30 Oxide 3,387,677 0.726 79,073
0.36 Transition 606,280 0.771 15,029
0.40 Sulphide 12,979,141 0.840 350,522
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Subtotal 16,973,098 0.815 444,624
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NAMI Indicated 0.30 Oxide 589,863 1.040 19,723
0.36 Transition 802,106 0.867 22,358
0.40 Sulphide 1,697,127 0.900 49,107
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Subtotal 3,089,096 0.918 91,189
Inferred 0.30 Oxide 138,466 0.866 3,855
0.36 Transition 171,673 0.800 4,416
0.40 Sulphide 653,217 0.677 14,218
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Subtotal 963,356 0.726 22,489
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RAMBO Indicated 0.30 Oxide 194,539 2.249 14,067
0.36 Transition 267,048 2.804 24,075
0.40 Sulphide 448,216 2.203 31,746
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Subtotal 909,803 2.389 69,887
Inferred 0.30 Oxide 177,857 1.070 6,118
0.36 Transition 88,954 0.636 1,819
0.40 Sulphide 785,743 1.165 29,430
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Subtotal 1,052,554 1.104 37,368
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TOTAL Indicated 0.30 Oxide 19,160,789 0.932 574,432
0.36 Transition 6,697,904 1.092 235,248
0.40 Sulphide 28,210,294 1.063 963,852
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Total 54,068,987 1.020 1,773,532
TOTAL Inferred 0.30 Oxide 6,535,264 0.701 147,322
0.36 Transition 1,620,817 0.704 36,700
0.40 Sulphide 29,194,854 0.825 774,525
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Total 37,350,935 0.798 958,547
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Assay data used as a basis in these resource estimates have been independently verified from original assay lab certificates.
The mineral resource estimates in this press release were prepared by Eugene Puritch, P.Eng. and Antoine Yassa, P.Geo., of P&E Mining Consultants Inc. ('P&E') of Brampton, Ontario, independent qualified persons, as defined by National Instrument 43-101.
An NI 43-101 compliant technical report supporting this mineral resource estimate will be completed by P&E Mining Consultants and filed on SEDAR within 45 days of the date of this press release. Mr. Puritch and Mr. Yassa have reviewed and approved the contents of this news release. Giles Peatfield Ph.D. P.Eng., is the Riverstone Qualified Person for the purposes of NI 43-101 and has approved the technical content of this news release.
Riverstone Resources Inc. is active in gold exploration in Burkina Faso, West Africa, where the company holds an extensive portfolio of three high quality exploration projects covering +1,400 square kilometres. The Goulagou permit is subject to an option to purchase agreement with Golden Star Resources. Riverstone has given formal notice of Exercise of the Option Agreement on December 23, 2011 to Golden Star Resources. For further information about the company and its activities, please refer to the company's website at www.riverstoneresources.com and under the Company's profile at www.sedar.com.
ON BEHALF OF THE BOARD
Michael D. McInnis, P. Eng.
Chairman & CEO
Giles. R. Peatfield, Ph.D., P.Eng. is a Qualified Person for RVS and has reviewed and approved the contents of this release.
Certain statements made and information contained in this news release and elsewhere constitutes 'forward-looking information' within the meaning of the Ontario Securities Act. Forward-looking statements are subject to a variety of risks and uncertainties which could cause actual events or results to differ from those reflected in the forward-looking statements, including, without limitation, risks and uncertainties relating to the interpretation of drill results and the estimation of mineral resources, the geology, grade and continuity of mineral deposits, the possibility that future exploration, development results will not be consistent with the Company's expectations, accidents, equipment breakdowns, title matters and surface access, labour disputes, the potential for delays in exploration activities, the potential for unexpected costs and expenses, commodity price fluctuations, currency fluctuations, failure to obtain adequate financing on a timely basis and other risks and uncertainties, including those described under Risk Factors in each management discussion and analysis. In addition, forward-looking information is based on various assumptions including, without limitation, the expectations and beliefs of management, the assumed long term price of gold, that the Company will receive required permits and access to surface rights, that the Company can access financing, appropriate equipment and sufficient labour and that the political environment within Burkina Faso will continue to support the development of environmentally safe mining projects. Should one or more of these risks and uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described in forward-looking statements. Accordingly, readers are advised not to place undue reliance on forward-looking statements.
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:
Riverstone Resources Inc. - Vancouver Office
Dwayne L. Melrose, President
604-801-5020
info@riverstoneresources.com
Riverstone Resources Inc.
Don Mosher, Corporate Development
604-685-6465
Riverstone Resources Inc.
Raju Wani, Investor Relations
403-240-0555
Riverstone Resources Inc.
Ron Cooper, Investor Relations
604-986-0112
www.riverstoneresources.com
