August 13, 2008

Riverstone Continues to Expand Gold Mineralization at Karma

VANCOUVER, BRITISH COLUMBIA--(Marketwire - Aug. 12, 2008) - Riverstone Resources Inc. (TSX VENTURE:RVS)(FRANKFURT:3RV) is pleased to report that the latest results of drilling continue to extend the known near-surface gold mineralization on the Kao Main Zone. Riverstone has completed a fifth phase of shallow reverse circulation (RC) drilling at Kao, which forms part of the Company's Karma Project in Burkina Faso. Results include:

- 11.18 g/t gold over 8 m

- 2.56 g/t gold over 10 m (including 5.67 g/t gold over 4 m)

- 1.48 g/t gold over 28 m

- 1.51 g/t gold over 14 m

A total of 167 holes have been drilled to date on a grid at the Kao Main Zone where a shallow, gold mineralized zone some 800 metres by 400 metres has been identified. The latest results confirm continuation of the extension of near-surface gold mineralization to the northeast. The mineralized zone is still open to the north, to the northeast, to the southwest, and at depth (see attached map). In view of these encouraging results, six additional holes are being drilled to test the emerging northeast trend to the deposit.

This current phase of RC drilling comprised 2,064 metres in 17 drill holes drilled at -60 degrees. Most holes were limited to 100 metres in length with each hole covering a vertical depth of approximately 87 metres. The main objective of the program was to determine further extensions of the shallow oxide gold mineralization at the Kao Main Zone, particularly to the north and northwest, in preparation for an independent resource estimate. A secondary objective of the program was to provide material for metallurgical test work. Wardrop Engineering Inc. will undertake the resource estimate and supervise the metallurgical test work (see news release dated July 10, 2008).

Significant results from the drilling program are summarized in the table below.

--------------------------------------------------------- Hole______________From________To__Hole Interval____ Grade Number________ (metres)__(metres)______ (metres)__(g/t Au) --------------------------------------------------------- KAO-08-RC-151______ 96______ 124____________ 28______1.48 --------------------------------------------------------- KAO-08-RC-152______ 64________74____________ 10______1.06 --------------------------------------------------------- KAO-08-RC-153______118______ 138____________ 20______1.36 --------------------------------------------------------- KAO-08-RC-154______ 86______ 108____________ 22______0.66 ____including______ 86________90______________4______1.20 or including______102______ 108______________6______1.32 --------------------------------------------------------- KAO-08-RC-155______ 80______ 112____________ 32______0.86 --------------------------------------------------------- KAO-08-RC-158______ 16________34____________ 18______0.83 ____including______ 22________26______________4______1.97 __________and______116______ 126____________ 10______2.56 ____including______116______ 120______________4______5.67 --------------------------------------------------------- KAO-08-RC-160________6________ 8______________2______1.99 __________and______ 18________44____________ 26______1.04 ____including______ 34________40______________6______2.37 --------------------------------------------------------- KAO-08-RC-161______ 18________22______________4______1.17 __________and______ 38________46______________8____ 11.18 __________and______ 94______ 108____________ 14______1.51 --------------------------------------------------------- KAO-08-RC-162______ 76________84______________8______1.43 --------------------------------------------------------- KAO-08-RC-163______ 32________36______________4______1.21 __________and______ 76________78______________2______1.05 --------------------------------------------------------- KAO-08-RC-165______ 10________18______________8______1.16 __________and______ 52________62____________ 10______0.85 ---------------------------------------------------------

All holes were drilled at -60 degrees. Intervals reported are drilled intercepts, which may not represent true widths of the mineralized zones.

In addition to drilling at the Kao Main Zone, the Company also drilled on the adjacent Goulagou and Rambo permits at the Company's Karma project and results will be released when assays have been received and verified. The Kao Main Zone and Goulagou deposits are approximately 12 kilometres apart, separated by flat terrain, with Rambo essentially midway between.

The contiguous Kao, Goulagou, Rambo and Rounga permits make up the Company's Karma project. Goulagou contains a NI 43-101 compliant indicated resource of 280,000 ounces of gold at a grade of 1.70 g/t and a further inferred resource of 270,000 ounces of gold at a grade of 1.49 g/t (see news release dated October 11, 2007). The Company's strategy is to develop sufficient gold resources within the Karma project area to support a mining operation utilizing a central processing plant. Riverstone has an initial target of developing at least 1,000,000 to 1,250,000 ounces of gold at Karma by late 2008 (see note below).

The Company maintains a rigorous quality control program involving the use of repeat assays, inserted blanks, and the use of verifiable standards from an accredited Canadian laboratory. All RC samples were assayed using standard fire assay with atomic absorption techniques, with samples grading in excess of 2.00 g/t gold 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.

Riverstone Resources Inc. is active in gold exploration in Burkina Faso, West Africa, where the company holds an extensive portfolio of high quality exploration permits covering 3,500 square kilometres. For further information about the company and its activities, please refer to the company's website at and under the Company's profile at


Michael D. McInnis, P.Eng., CEO & President

Note: The target estimate of at least 1,000,000 to 1,250,000 ounces of gold is based on the potential for gold resources in all categories of some 20 to 25 million tonnes containing an estimated average of 1.5 g/t gold which in turn is based on a reasonable projection of the results to date from drilling the mineralized zones on the Goulagou, Kao and Rambo permits at Karma and from the existing NI 43-101 resource estimates for the Goulagou deposits. The figures are intended to provide an indication of management's expectations and are conceptual in nature. To date, insufficient exploration has been undertaken to define this size of mineral resource and therefore it is uncertain whether the target will be delineated as a mineral resource or whether production will ensue.

Paul G. Anderson, P. Geo is a Qualified Person for RVS and has reviewed and approved the contents of this release.

To view accompanying map, please click on the following link:

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.

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