Mariana Resources Completes Purchase of Sierra Blanca JV Interest in Argentina

VANCOUVER, BRITISH COLUMBIA -- (Marketwire) -- 02/24/12 -- Mariana Resources Ltd. (TSX: MRY)(AIM: MARL)(PLUS: MARL) ('Mariana' or 'the Company'), the AIM and TSX quoted exploration and development company focused in Argentina and Chile, announces that it has completed the purchase of the remaining interest in the 7,000 Ha Sierra Blanca Gold-Silver Project located in the Deseado Massif of the Santa Cruz Province, southern Argentina from IAMGOLD Corp. ('IAMGOLD'). The project is now 100% owned by Mariana, subject to a 1.5% royalty to IAMGOLD on a net smelter returns basis.

Exploration to date at Sierra Blanca, approximately 50km from AngloGold Ashanti's Cerro Vanguardia project, confirms broad target zones at Vetarron, Lucila and Achen-Chala along a combined 8.9km trend which could host structurally controlled high grade gold-silver mineralisation. Vetarron Norte is emerging as a new target area both in terms of strike and depth potential. Further exploration will be guided by structural and alteration mapping and detailed ground magnetics, and review by the technical committee formed by AngloGold Ashanti and Mariana.

This second equal tranche of the purchase option comprised a USD$250,000 payment and the issue of 1,639,339 shares at 9.71p per share, which is the 15 day volume weighted average price of Mariana shares on AIM. The shares were issued on 24th. February 2012 and are expected be admitted to trading on AIM on 29th. February 2012. Although the shares have been granted listing on the TSX, the shares are not permitted to be sold in Canada or to a Canadian resident before 25th. June 2012.

The first equal tranche of the purchase option was completed on 18 November 2011 with the payment of US$250,000 and issue of 1,687,345 shares at 9.41 pence per share.

Under the placing agreement between Mariana and AngloGold Ashanti Holdings PLC ('AGA'), AGA has the right to maintain its equity interest in Mariana at 19.89%. (See announcement on 17 November 2011). AGA has exercised this right, which means that a further 406,147 shares have been issued to AGA, also at 9.71p per share. These shares similarly are subject to trading restrictions in Canada until 25th. June 2012.

Following these issues the issued capital of the Company is 230,785,973 fully paid GBP 0.0001 shares.

For further information please visit website at www.marianaresources.com.

About Mariana Resources

Mariana Resources Ltd. is an AIM and TSX quoted exploration and development company with an extensive portfolio of gold, silver and copper projects in Argentina and Chile. In southern Argentina, in addition to the advanced Las Calandrias gold-silver project, the Company has the Sierra Blanca silver-gold project (100%); the Los Amigos joint venture (49%) with Hochschild Mining and staked a 215,000 Ha land package (100%) . All of these projects are located in the Deseado Massif epithermal gold-silver district in mining-friendly Santa Cruz province of southern Argentina, which hosts four mines and several advanced projects. In Chile, Mariana has a joint venture with US based international mining and natural resources company Cliffs Natural Resources Inc., to explore for iron oxide-copper-gold deposits ('IOCG') in a 92,000 km2 area ('SCM Mariana Area') in north-central Chile along the highly prospective Atacama Fault Zone. The SCM Mariana Area includes the 44km2 Buenaventura and 46km2 Perro Chico IOCG projects. Mariana is also evaluating a number of gold-silver and copper-gold opportunities independent of and outside the Cliffs JV area.

Incorporated in Guernsey registered number 44276.

Safe Harbour

This press release presents 'forward-looking statements' within the meaning of Canadian securities legislation that involve inherent risks and uncertainties. Forward-looking statements include, but are not limited to, statements with respect to the future price of gold and other minerals and metals, the estimation of mineral resources, the capital expenditures, costs and timing of the resources, the realization of mineral reserve estimates, the capital expenditures, costs and timing of the development of new deposits, success of exploration activities, permitting time lines, currency exchange rate fluctuations, requirements for additional capital, government regulation of mining operations, environmental risks, unanticipated reclamation expenses, title disputes or claims and limitations on insurance coverage. Generally, these forward-looking statements can be identified by the use of forward looking terminology such as 'plans', 'expects' or 'does not expect', 'is expected', 'budget', 'scheduled', 'estimates', 'forecasts', 'intends', 'anticipates' or 'does not anticipate', or 'believes', or variations of such words and phrases or state that certain actions, events or results 'may', 'could', 'would', 'might' or 'will be taken', 'occur' or 'be achieved'. Forward-looking statements are subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of Mariana to be materially different from those expressed or implied by such forward looking statements, including but not limited to: risks related to international operations, actual results of current exploration activities; actual results of current or future reclamation activities; conclusions of economic evaluations; changes in project parameters as plans continue to be refined; future prices of gold and other minerals and metals; possible variations in ore reserves, grade or recovery rates; failure of equipment or processes to operate as anticipated; accidents, labour disputes and other risks of the mining industry; and delays in obtaining governmental approvals or financing or in the completion of development or construction activities. Although the management of Mariana believes that the expectations reflected in such forward-looking statements are based upon reasonable assumptions and have attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended.

There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. Mariana Resources does not undertake to update any forward-looking statements that are incorporated by reference herein, except in accordance with applicable securities laws.

Neither the TSX nor its Regulation Services Provider (as that term is defined in the policies of the TSX Exchange) accepts responsibility for the adequacy or accuracy of this news release.

Contacts:

Mariana Resources Ltd.

John Horsburgh

Chairman

+61 2 9437 4588


Mariana Resources Ltd.

Glen Parsons

CFO

+612 9437 4588


RFC Corporate Finance Limited (Nomad)

Rob Adamson

+61 2 9250 0041


RFC Corporate Finance Limited (Nomad)

Will Souter

+61 2 9250 0050


FinnCap (Broker)

Matthew Robinson

+44 20 7600 1658


Fox Davies Capital (Co UK Broker)

Jonathan Evans

+44 20 3463 5000


St Brides Media and Finance Ltd. (PR)

Felicity Edwards

+44 20 7236 1177


St Brides Media and Finance Ltd. (PR)

Elisabeth Cowell

+44 20 7236 1177


Mariana Resources Ltd. (Vancouver Office)

Kathryn Witter

+1 604 669 9336
www.marianaresources.com


Renmark Financial Communications (PR)

Arash Shahi

+1 514 939 3989


Renmark Financial Communications (PR)

Philip Robin

+1 416 644 2020