September 18, 2008

Riverstone Extends Gold Mineralization at Karma

VANCOUVER, BRITISH COLUMBIA--(Marketwire - Sept. 18, 2008) - Riverstone Resources Inc. (TSX VENTURE:RVS)(FRANKFURT:3RV) is pleased to report results from recent reverse circulation (RC) drilling on the Goulagou, Rambo and Kao deposits, which are part of the Company's Karma Project in Burkina Faso, West Africa. The Company continues to intersect good gold values over substantial intervals in all three deposits. All of the deposits remain open in at least one direction and at depth.

Significant results from the drilling program are summarized in the table below. The Rambo and Kao holes were drilled at -60 degrees and the Goulagou holes at -55 degrees. Intervals reported are drilled intercepts, which may not represent true widths of the mineralized zones. -------------------------------------------------------------------- ------ ____________________________________________________________ Hole __________________________________________From______ To__Interval____Grade Deposit____Hole Number________________ (metres) (metres)__(metres) (g/t Au) -------------------------------------------------------------------- ------ Goulagou__ RVS-GLG-08-RC-026______________ 118______134________16____ 1.56 __________ including______________________ 124______132________ 8____ 2.51 __________ and____________________________ 158______160________ 2____ 1.19 __________ (hole stopped at 160 metres; ____________last sample 1.19 g/t) -------------------------------------------------------------------- ------ Goulagou__ RVS-GLG-08-RC-027________________18______ 60________42____ 1.55 __________ including________________________30______ 42________12____ 3.13 -------------------------------------------------------------------- ------ Goulagou__ RVS-GLG-08-RC-028______________ 146______160________14____ 1.05 -------------------------------------------------------------------- ------ Goulagou__ RVS-GLG-08-RC-034________________16______ 42________26____ 0.42 __________ and______________________________42______ 70________28____ 2.30 -------------------------------------------------------------------- ------ Rambo______RA-08- 17________________________106______120________14____ 3.02 -------------------------------------------------------------------- ------ Kao________KAO-08-RC 173____________________58______ 68________10____ 1.99 Main______ and including____________________92______ 98________ 6____ 1.01 -------------------------------------------------------------------- ------

The Goulagou drilling totaled 1,285 metres, comprising 5 holes at Goulagou 1 (GG1) and 4 at Goulagou 2 (GG2). The drilling was designed to follow up on excellent results obtained earlier this year on GG2 (see news release dated May 7, 2008). Both zones continue to be expanded along strike and at depth. The results at GG2 are particularly significant, considering the fact that all of the holes were stopped before reaching their planned depth, due to a combination of bad ground and increased water pressure due to the rapidly rising water table during the rainy season.

Only a single 106 metre hole was drilled at Rambo due to the onset of the rainy season. The intersection of 3.02 g/t gold over 14 m confirms the high grade nature of this zone, which was last drilled by the Company in 2005. The Rambo zone remains open along strike and at depth, and a number of attractive drill targets exist nearby.

Six further holes were drilled at Kao Main, totaling 660 metres. These holes confirm that the known near-surface gold mineralization is still open to the north and to the northeast. The gold mineralized zone has been identified over a distance in excess of 800 metres by 400 metres, and is also open below 85 metres vertically.

The Company is currently preparing to undertake an independent resource estimate on all three deposits. This recent drilling has also provided material for metallurgical test work, which will begin shortly. Wardrop Engineering Inc. will undertake the resource estimate and supervise the metallurgical test work (see news release dated July 10, 2008).

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. The Kao Main Zone and Goulagou deposits are approximately 12 kilometres apart, separated by flat terrain, with Rambo essentially midway between. 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.

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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