TORONTO, ONTARIO--(Marketwire - Feb. 23, 2012) - Thundermin Resources Inc. ("Thundermin") (News - Market indicators) and 50% joint venture partner Cornerstone Resources Inc. (TSX VENTURE:CGP) announce that they have intersected 2.8% Cu over a core length of 18.2 m, including 5.2% Cu over 4.2 m and 3.4% Cu over 3.5 m, in an on-going initial Diamond drilling program on their 100% owned, past-producing Whalesback Copper Mine ("Mine"). The Mine, which was in production from 1965 - 1972, is located approximately 10 km north of Springdale in north-central Newfoundland and approximately 800 m north of the 100% owned Little Deer Copper Deposit ("Deposit") (see Figure 1 and Table 1).

Table 1: Whalesback Drill Results (2011-2012)

The purpose of the current drill program, comprising approximately 4,000 metres of drilling in 13-15 holes, is to discover additional copper resources at relatively shallow depths adjacent to the Mine below and to the west of the old mine workings and to confirm historical drill intercepts in undeveloped areas of the Mine for the purposes of National Instrument 43-101 ("NI 43-101"). A digital compilation of historical Diamond drill hole assay data recovered from the archives of the Newfoundland and Labrador Department of Natural Resources in St. John's suggests that there is excellent potential for the discovery of additional copper resources at the Mine (see news release dated October 20, 2011). The discovery of any new copper resources at the Mine could, because of their proximity to the Deposit, expand the total mineral resources available for mining and enhance the overall economics of establishing a new mining operation at Little Deer. At this time, the potential discovery of additional mineral resources at the Mine is conceptual in nature and it is uncertain whether further Diamond drilling will result in the discovery of additional mineral resources.

All holes completed to date have intersected copper mineralization with the most significant copper intervals being in holes 104, 105 and 101 (see Table 1 and Figure 1). Hole WB-12-104 intersected 2.8% Cu over a core length of 18.2 m, including 5.2% Cu over 4.2 m and 3.4% Cu over 3.5 m. This hole was drilled to confirm the copper mineralization intersected in historical hole 9-43 which assayed 4.0% Cu over 3.4 m and 4.5% Cu over 6.1 m and for which no assay data was available in the historical drill log. Hole WB-12-105 intersected 7.5% Cu over 0.4 m and 1.6% Cu over 7.0 m, including 2.2% Cu over 3.0 m. This intersection, which is the easternmost hole drilled to date at this depth on the Mine, occurs 90 m below hole 104 and 50 m east of historical hole 11-12 which intersected 1.6% Cu over 5.8 m. Hole WB-11-101 intersected 3.4% Cu over 1.7 m at a depth of approximately 75 m below surface, west of the area mined previously. The drill results to date confirm historical copper intercepts and suggest that the Whalesback deposit remains open to the east, west and at depth.

Preliminary Economic Assessment ("PEA") - Little Deer Copper Deposit

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

Mineral Resource Estimate - Little Deer Copper Deposit

On June 22, 2011, Thundermin and Cornerstone reported a NI 43-101 compliant mineral resource estimate for the Deposit comprising Indicated Resources of 1,911,000 tonnes at an average grade of 2.37% Cu (99.8 million pounds of copper) and Inferred Resources of 3,748,000 tonnes at an average grade of 2.13% Cu (175.9 million pounds of copper). The mineral resource estimate was 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.

Qualified Person

Mr. Andrew Hussey, P.Geo., Project Geologist and Lands Manager, Cornerstone Resources Inc., is the Q.P. responsible for supervising the drilling program 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 the Deposit and the terms of the agreement with Cornerstone can be found in numerous news releases between May 1, 2007 and November 1, 2011 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 thirteen 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.

For further information on Thundermin Resources Inc. please visit Thundermin's website at www.thundermin.com or the SEDAR website at www.sedar.com.

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