TORONTO, ONTARIO--(Marketwire - May 10, 2012) - Thundermin Resources Inc. ("Thundermin") (News - Market indicators) and 50% joint venture partner Cornerstone Resources Inc. ("Cornerstone") (TSX VENTURE:CGP) announce that a recently completed, 6,198 m, 14 hole drill program on the 100%-owned, past-producing Whalesback Copper Deposit ("Whalesback") has extended the deposit to a vertical depth of 625 m below surface and from 50-100 m to the east and west of the historical deposit strike length at depths of 400-525 m below surface (see Figure 1 and Table 1). This new mineralization is expected to increase the total mineral resource available for mining and enhance the economics of establishing a new copper mining and milling operation at the adjacent Little Deer Copper Deposit ("Little Deer") which is estimated to contain National Instrument 43-101 ("NI 43-101") compliant Indicated Resources of 1,911,000 tonnes grading 2.37% Cu (99.8 million pounds of copper) and Inferred Resources of 3,748,000 tonnes grading 2.13% Cu (175.0 million pounds of copper). Whalesback is located approximately 10 km north of Springdale in north-central Newfoundland and approximately 800 m north of Little Deer.

The results of the drilling program at Whalesback include: 1.1% Cu over a core length of 8.4 m and 3.4% Cu over 2.3 m in hole WB-12-108, approximately 75 m below historical hole 11-11 which intersected 1.7% Cu over 8.4 m; 1.2% Cu over 5.6 m in hole WB-12-106A, approximately 100 m east of hole 11-11; and 2.7% Cu over 3.1 m, 2.1% Cu over 4.4 m and 1.6% Cu over 1.9 m in hole WB-12-111, approximately 50 m east of historical hole 11-2 which intersected 1.9% Cu over 2.6 m. Previously reported hole WB-12-105 intersected 7.5% Cu over 0.4 m, 1.6% Cu over 7.0 m and 2.2% Cu over 3.0 m approximately 40 m east of historical hole 11-12 which intersected 1.6% Cu over 5.8 m. In addition, previously reported hole WB-12-104, which intersected 2.8% Cu over 18.2 m, including 5.2% Cu over 4.2 m, 3.4% Cu over 3.5 m and 2.6% Cu over 2.0 m, confirmed historical grades of 4.0% Cu over 3.4 m and 4.5% Cu over 6.1 m in hole 9-43 for the purposes of NI 43-101. The results of this drilling suggest that the copper mineralization at Whalesback remains open to the east, west and at depth.

Future work at Whalesback will include borehole Pulse EM surveys on 5-6 of the recently completed drill holes to help direct future drilling at depth, GPS surveying and a NI 43-101 compliant mineral resource estimate for the deposit. This work is scheduled to commence in the next couple of weeks.

Little Deer Copper Property Exploration Plan

A 223 line kilometre VTEM airborne survey carried out in 2008 east of the Little Deer and Whalesback copper deposits identified a number of untested conductors that appear to be within geology favorable as a host to base metal deposits. Thundermin and Cornerstone intend to undertake ground geophysical surveys over these conductors this summer and have budgeted for approximately 2,000 m of follow-up Diamond drilling to test the best of these conductors.

Little Deer Copper Deposit Plans

On November 1, 2011, Thundermin and Cornerstone announced positive results from a Preliminary Economic Assessment ("PEA") for the Little Deer. The PEA indicated that there is potential to develop Little Deer on an attractive economic basis at current copper prices (see news release dated November 1, 2011 and Technical Report filed on SEDAR on December 15, 2011).

Thundermin and Cornerstone plan, subject to financing, to initiate an infill Diamond drilling program at Little Deer commencing in September 2012. This program will consist of approximately 7,000 m of drilling in 9-10 holes in the eastern, higher grade, portion of Little Deer to be followed up by additional infill drilling in 2013 in other areas of the deposit. This work is designed to upgrade the Inferred Resources to the Indicated Resource category in order that a pre-feasibility study can be undertaken on the deposit.

Qualified Persons

The mineral resource estimate and PEA referred to above were prepared under the supervision of Mr. Eugene J. Puritch, P. Eng., President of P&E Mining Consultants Inc. of Brampton, Ontario. Mr. Puritch is an independent Qualified Person ("Q.P.") in accordance with NI 43-101.

Mr. Andrew Hussey, P.Geo., Project Geologist and Lands Manager, Cornerstone Resources Inc., is the Q.P. responsible for supervising the drilling program at Whalesback for the purposes of NI 43-101. All holes drilled by Thundermin and Cornerstone are NQ in size. Bulk density measurements, rock quality designations and photographic logging of significant mineralized intersections are performed systematically prior to assaying. The core is logged and the mineralized sections, where appropriate, are sawn in half at a core logging facility in Springdale. Half of the core is submitted for analyses to Eastern Analytical Limited, an independent and qualified assayer located in Springdale, Newfoundland and the remaining half of the core is kept for future reference. Blanks, duplicates and standards are routinely used as part of the assay procedures.

Little Deer Joint Venture

Under the terms of its joint venture agreement with Cornerstone, Thundermin has the right to increase its interest in the Little Deer property to 75% by completing a feasibility study and by arranging 100% of the necessary bank financing required to place the property into commercial production. Details on Little Deer and Whalesback and the terms of the agreement with Cornerstone can be found in numerous news releases between May 1, 2007 and February 23, 2012 and on Thundermin's and Cornerstone's respective websites and on SEDAR.

About Thundermin

Thundermin is a Canadian-based mineral exploration company focused on the exploration for and the discovery of economically viable base metal and gold deposits in Canada. Thundermin has an interest in, or the right to earn an interest in 12 base metal and gold properties in Canada. Thundermin owns a 100% interest in the Lebel Township gold property, which is located on the Kirkland Lake Main Break in the prolific Kirkland Lake gold camp. Thundermin recently acquired the right to earn a 100% interest in eight exploration licenses covering a large portion of the Stirling volcanogenic massive zinc-lead-copper-silver-gold sulphide belt located on Cape Breton Island, Nova Scotia. Thundermin has royalty interests in 28 base metal and gold properties located in Manitoba, Saskatchewan, British Columbia and Quebec, the most significant being a 2.5% net smelter return royalty in the Pelletier Lake gold deposit which is under option to Alexis Minerals Corporation. Thundermin also has various shareholdings in fourteen other junior resource companies that are actively exploring for base metal, gold, chrome, vanadium-titanium and Diamond deposits in Canada.

Forward-Looking Statements

This news release may contain "Forward-Looking Statements" that involve risks and uncertainties, such as statements of Thundermin's plans, objectives, strategies, intentions and expectations. The words "potential", "anticipate", "forecast", "believe", "estimate", "expect", "may", "project", "plan", and similar expressions are intended to be among the statements that identify "Forward-Looking Statements". Although Thundermin believes that its expectations reflected in these "Forward-Looking Statements" are reasonable, such statements may involve unknown risks, uncertainties and other factors disclosed in our regulatory filings that can be viewed on the SEDAR website at www.sedar.com. For us, uncertainties arise from the behavior of financial and metals markets and from numerous other matters of national, regional, and global scale, including those of an environmental, climatic, natural, political, economic, business, competitive, or regulatory nature. These uncertainties may cause our actual future results to be materially different than those expressed in our "Forward-Looking Statements". Although Thundermin believes the facts and information contained in this news release to be as correct and current as possible, Thundermin does not warrant or make any representation as to the accuracy, validity or completeness of any facts or information contained herein and these statements should not be relied upon as representing its views subsequent to the date of this news release.

E-mail: info@thundermin.com or visit Thundermin's website at www.thundermin.com or the SEDAR website at www.sedar.com.

To view accompanying Figure 1, visit the following link: http://media3.marketwire.com/docs/Figure1_THR510.pdf