Calvista Reports Inferred Resource Estimate for Its California Project

TORONTO, ONTARIO--(Marketwire - May 25, 2012) - Calvista Gold Corporation (TSX:CVZ) ("Calvista" or the "Company") is pleased to announce the completion of a technical report and an initial mineral resource estimate for the Callejón Blanco and Buenavista prospects located along the same mineralized trend as the multi-million ounce Angostura gold deposit owned by Eco Oro Minerals, as well as La Mascota and La Bodega gold deposits owned by AUX Canada Acquisition Inc.

The Company's Chief Executive Officer, Mr. Mark Haywood stated that, "the Company is very pleased with the results of our first phase of drilling to produce an estimated 510,087 ounce inferred gold resource at a 1 g/t gold cut-off grade within 12 months of our Initial Public Offering. A second phase of drilling is currently underway with results expected in Quarter 3, 2012."

Highlights of the technical report:

• An inferred mineral resource estimate of 8.0 million tonnes grading 2.25 grams per tonne ("g/t") of gold and 12.60 g/t of silver (approximately 510,087 ounces of gold and 2,856,489 ounces of silver) using a cut- off grade of 1.0 g/t of gold;
  
  
• The Callejón Blanco and Buenavista targets remain open to expansion both along strike and at depth;
  
  
• The highest point of our inferred mineral resource occurs more than 500 metres below the Páramo ecosystem elevation limit of 3,200 metres above sea level; and
  
  
• The technical report and inferred mineral resource estimate was completed by Vadim Galkine, Ph.D., P. Geo., and is based upon 38 diamond drill holes totalling 15,054 metres of core and wireframes surrounding the drill holes.
  
  

The Callejón Blanco and Buenavista targets are considered to have the hallmarks of a porphyry Cu±Mo±Au style deposit, with gold hosted in a hydrothermal breccia near the surface, in an intrusive as disseminated mineralization, and also associated with corroded quartz veins and sometimes with sulphide mineralization.

The Inferred Mineral Resource estimate is presented for various gold cut-off grades. Highlighted in red, in the Table below, is the cut-off grade considered to be the most appropriated for this target. The resources were estimated using a dry density of 2.4 g/cm³ and a minimum thickness of 1.5 metres.

To view the table associated with this press release, please visit the following link: http://media3.marketwire.com/docs/Calvista0525.pdf.

The mineral resources in the technical report were estimated using the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") Standards on Mineral Resources and Reserves, Definitions and Guidelines prepared by the CIM Standing Committee on Reserve Definitions.

Mineral resources which are not mineral reserves do not have demonstrated economic viability. Confidence in a mineral resource estimate is insufficient to allow the meaningful application of technical and economic parameters or to enable an evaluation of economic viability worthy of public disclosure. The estimate of mineral resources may be materially affected by environmental, permitting, legal, title, taxation, sociopolitical, marketing, or other relevant issues.

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. Inferred Mineral Resources must be excluded from estimates forming the basis of feasibility or other economic studies.

Mineral Resource Estimation Methodology

Gold grade shells (or wireframes) were constructed by extrapolation of the shells to a limit of 50 metres beyond each drill hole to constrain the estimation. The processing and interpretations of the resource estimation were completed by an independent consultant, Eng Abdiel Diaz Carmona, Ph.D., in collaboration with the Company's Qualified Person, then tested and independently confirmed by Dr. Galkine. Block grade estimation was carried by Ordinary Kriging within the wireframes. The specific densities of the rock types were estimated at 2.4 g/cm³ and all samples were composited into a constant length of 1.5 metres. The block model cells size used was 25 x 25 x 10 metres, considered an appropriate volumetric representation for this style of mineralization.

Calvista will file within 45 days a National Instrument 43-101 compliant technical report with the applicable securities regulatory authorities that supports the technical information contained herein, which will be available for viewing under the corporate profile of Calvista Gold Corporation at www.sedar.com.

Páramo Ecosystem

The Páramo is an ecosystem generally above 3,200 metres elevation consisting of glacier-formed valleys and plains with lakes, peat bogs, and wet and dry grasslands intermingled with shrub lands and forest patches. Law 1382 of 2010 which amended the existing Mining Code excludes and prohibits mining and exploration activities in areas of Páramo ecosystem. All the company's mining licences are below the Páramo ecosystem limit and the Company has received certification to that extent from the Corporacion de Defensa de la Meseta de Bucaramanga, the local environmental authority of the Department of Santander, Colombia.

Quality Control and Reports

The Company has developed and implemented a Quality Assurance and Quality Control program ("QA&QC") to ensure sampling and analysis of all exploration work is conducted in accordance with the best possible practices. Calvista's exploration protocol includes the insertion of blanks, duplicates, standards, and external controls on all samples. Samples with assay results greater than 10 g/t Au are re-assayed by metallic screen analysis. Sample preparation for the technical report was conducted by SGS Colombia S.A. in Medellin, Colombia before being analyzed at a SGS certified assay laboratory in Lima, Peru.

Qualified Persons

Mr. Ricardo Valls, P. Geo., Calvista's VP Exploration, is the Company's designated Qualified Person for this press release within the meaning of National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43- 101") and has reviewed and validated that the technical information contained in the release is accurate. Vadim Galkine, Ph.D., P. Geo., author of the technical report, acknowledges that he has read this press release and approves of its contents.

About Calvista

Calvista is a mineral exploration company focused on the acquisition, exploration and development of properties for the mining of gold and other minerals. All the Company's prospects in the California Valley are located below 3,200 metres and are not affected by the Páramo ecosystem law. With a head office in Toronto and Colombian headquarters in Bucaramanga, Calvista is led by a management team with over 50 years of exploration and mining experience, principally in South and Central America. For further details on the Company, please refer to Calvista's website (www.calvistagold.com) and Calvista's Canadian regulatory filings on SEDAR at www.sedar.com.

CAUTIONARY STATEMENT: This press release contains forward-looking information which is not comprised of historical facts. Forward-looking information involves risks, uncertainties and other factors that could cause actual events, results, performance, prospects and opportunities to differ materially from those expressed or implied by such forward-looking information. Forward looking information in this press release includes, but is not limited to, Calvista's objectives, goals or future plans, statements regarding exploration results and exploration plans. Factors that could cause actual results to differ materially from such forward-looking information include, but are not limited to, uncertainties inherent to preparing a resource estimate, failure to increase estimated mineral resources and failure to convert estimated mineral resources to reserves, capital and operating costs varying significantly from estimates, the preliminary nature of metallurgical test results, delays in obtaining or failures to obtain required governmental, environmental or other project approvals, political risks, uncertainties relating to the availability and costs of financing needed in the future, changes in equity markets, inflation, changes in exchange rates, fluctuations in commodity prices, delays in the development of projects and the other risks involved in the mineral exploration and development industry, enhanced risks inherent to conducting business in a jurisdiction such as Colombia, and those risks set out in Calvista's public documents filed on SEDAR. Although Calvista believes that the assumptions and factors used in preparing the forward-looking information in this news release are reasonable, undue reliance should not be placed on such information, which only applies as of the date of this news release, and no assurance can be given that such events will occur in the disclosed time frames or at all. Calvista disclaims any intention or obligation to update or revise any forward-looking information, whether as a result of new information, future events or otherwise, other than as required by law.