Mariana Resources-Appointment of New COO and Vice President of Exploration

VANCOUVER, BRITISH COLUMBIA -- (Marketwire) -- 12/05/11 -- Mariana Resources Limited ('Mariana' or 'the Company') (TSX: MRY)(AIM: MARL)(PLUS: MARL), the AIM quoted exploration and development company in Argentina and Chile, is pleased to announce that it is appointing Mr. Ray Angus, former Non-Executive Director, as Chief Operating Officer ('COO') and Dr. Gustavo Rodriguez, former Country Manager of Argentina for Mariana, as Vice President of Exploration ('VPE') with immediate effect.

Ray Angus will take on the Executive role of COO reporting to the Executive Chairman of the Company, John Horsburgh. His role will be to support management on overseeing operations in both Argentina and Chile. The main focus for 2012 will be advancing the Company's key Las Calandrias and Sierra Blanca gold-silver projects and the 225,000 Ha generative pipeline in Santa Cruz province, Argentina.

Ray has over 20 years global exploration and mining experience having graduated with a Bachelor of Applied Science - Applied Geology from Queensland University of Technology in 1987. This included previous positions with Cyprus Gold Australia and Newcrest Mining (Peru) and consulting to companies such as Goldfields and BHP Billiton. He was co-founder of former AIM-quoted Monterrico Metals and as Executive Director and COO, he was responsible for the acquisition and management of the Rio Blanco copper-molybdenum project in northern Peru for which a Feasibility Study based on a 1.26Bt at 0.57% Cu 228 ppm Mo resource and a 25Mtpa, 20 year mining scenario was reported. Monterrico was subsequently acquired by a Chinese Consortium lead by Zijin in 2007. He currently controls 5,504,300 shares in the Company which represents a 2.77% equity on a fully diluted basis.

Gustavo Rodriguez will take on a more expansive role as VPE, reporting to the COO and Executive Chairman. This appointment has been made in recognition of Gustavo's leadership and management of Mariana's successful exploration programmes in Argentina.

Gustavo graduated with BSc and PhD degrees in geology from University of Cordoba, Argentina. He has over 12 years of experience in Latin America with several companies including Sunshine Mining (former owner of Pirquitas mine), IAMGOLD Corp., and Crystallex International. As Crystallex's Chief Geologist, he managed advanced drilling at the Las Cristinas gold deposit in Venezuela. As Mariana Country Manager Argentina, Gustavo was instrumental in the acquisition of the Company's extensive land package in Santa Cruz, Southern Argentina and in the discovery of new gold-silver deposits at Las Calandrias and Sierra Blanca.

He is a Qualified Person ('QP') as defined by NI 43-101 standards for reporting and has been responsible for supervising resource estimations at Las Calandrias and preparation of technical news releases relating to drilling programmes. Gustavo is a member of the Australian Institute of Geoscientist (MAIG), a Fellow of the Society of Economic Geologists (FSEG), a member of the Society for Geology Applied to Mineral Deposits (SGA) and has been a Doctoral Fellow of the Argentinean Council for Scientific and Technical Research (CONICET)

Mariana Chairman John Horsburgh commented, 'These key appointments are significant developments for Mariana. Ray Angus adds considerable experience and expertise to the Executive team as the Company seeks to advance its exciting portfolio in Argentina and Northern Chile. We are also delighted that Gustavo Rodriguez has accepted this promotion to VPE as we continue to progress Santa Cruz projects with renewed vigour following the recent investment by AngloGold Ashanti in Mariana.'

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

About Mariana Resources

Mariana Resources Ltd is an AIM 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 Las Calandrias gold-silver discovery, the Company has the Sierra Blanca silver-gold prospect (100%); the Los Amigos joint venture (49%) with Hochschild Mining and a 160,000 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 away from the Cliffs JV area, as part of a new initiative.

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.

Contacts:

Mariana Resources Ltd

John Horsburgh (Chairman)

61 2 94374588


Mariana Resources Ltd

Glen Parsons (CFO)

612 94374588


Mariana Resources Ltd (Vancouver Office)

Kathryn Witter

1 604 669 9336
www.marianaresources.com


RFC Corporate Finance Limited (Nomad)

Rob Adamson

61 2 9250 0041


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Will Souter

61 2 9250 0050


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44 20 7600 1658


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Jonathan Evans

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