Coro Reports Resource Estimate for Berta Sur


VANCOUVER, BRITISH COLUMBIA--(Marketwire - Dec 6, 2012) - Coro Mining Corp. ("Coro" or the "Company") (COP.TO) is pleased to announce the results of an independent National Instrument 43-101 compliant resource estimate for the Berta Sur deposit on its Berta property, located approximately 20km west of the village of Inca de Oro, in the III Region of Chile. Coro announced preliminary metallurgical results from Berta Sur on November 5th 2012. The resource estimate was completed by Propipe SA, an engineering firm based in Santiago, Chile at a variety of total copper (%CuT) grades, as shown on Table 1, below.

Table 1: Resource Estimate
Cutoff  Measured   Indicated  Measured & Indicated  Inferred 
%CuT kt %CuT %CuS kt %CuT %CuS kt %CuT %CuS kt %CuT %CuS
0.10 10,672 0.32 0.21 7,725 0.17 0.10 18,397 0.26 0.17 6,465 0.16 0.10
0.15 8,498 0.37 0.25 4,250 0.21 0.13 12,748 0.31 0.21 3,705 0.19 0.12
0.20 6,736 0.42 0.29 1,814 0.25 0.16 8,550 0.38 0.26 1,363 0.23 0.14
0.25 5,254 0.47 0.33 691 0.31 0.20 5,945 0.45 0.31 265 0.27 0.17
0.30 4,170 0.53 0.37 261 0.37 0.24 4,431 0.52 0.36 21 0.32 0.20

In order to demonstrate the potential economic viability of the Berta Sur resource, a series of pit optimizations using the Lersch & Grossmann algorithm was then completed utilizing appropriate operating costs, results obtained from the Company''s previously announced preliminary metallurgical test work, and a variety of copper prices. For a $3.00/lb copper price, the optimum pit was determined to contain 6,101,000t at a grade of 0.40%CuT and a stripping ratio of 0.04:1. An upside case pit at $3.825/lb Cu contains 9,687,000t at 0.34%CuT and a stripping ratio of 0.16:1. The two pit outlines are shown on Figure 1, together with the Berta Central oxide zones, not included in the current resource estimate. A typical block model cross section is shown on Figure 2.

To view Figures 1 and 2 please click on the following link:

Alan Stephens, President and CEO of Coro commented, "We are pleased with the continued progress of our Berta project, where we have now demonstrated that the Berta Sur resource, while modest in size, has a negligible stripping ratio, with the further advantage that the preliminary metallurgy indicates quick copper recoveries and low acid consumptions. We see potential for additional resources on the property in the Berta Central deposits, and believe there may be potential elsewhere on the property and the surrounding district to augment these. Coro now intends to advance the project to the completion, by mid-late 2013, of a feasibility study for a standalone SXEW project with planned production of 5,000 tpy copper in cathode, with attached acid plant to supply all project power requirements."

Parameters Used in the Construction of the Mineral Resource

The NI 43-101 compliant mineral resource estimate was based on a total of 14,362.45 meters of drilling in 91 holes, (including reverse circulation (RC) drilling completed by 2 major companies in the 1990''s (23 holes); diamond drilling completed by Grancru Resources in 2007 (2 holes); and RC drilling (66 holes) completed by the Company in 2011-12); and a total of 938.6m of surface trenching in 11 trenches completed by one of the aforementioned major companies.

The mineral resource estimate has been generated from drill hole and trench sample assay results and the interpretation of a geologic model which relates to the spatial distribution of copper in the deposit. Grade estimates were made using ordinary kriging with nominal block size measuring 2.5 meters long, 2.5 meters wide and 2.5 meters in height. Resources have been classified by their proximity to sample locations and are reported according to CIM standards on Mineral Resources and Reserves.

The in pit mineral resource was constructed according to technical and economic parameters in Table 2, assuming the construction of a sulphur burning acid plant capable of generating the project''s power requirement.

Table 2: Technical and Economic Parameters
Mining $2.09/t
Processing $4.74/t
SX EW Cost $0.102/lb
G&A $0.045/lb
Sales and marketing $0.041/lb
Recovery 80%
Inter ramp pit slope 50°
Copper Price $3.00/lb

An updated NI 43-101 technical report detailing the mineral resource estimate will be completed and filed on SEDAR (, and Coro''s website (, within 45 days.

El Inca Project

Results have now been received from a program of reverse circulation and diamond drilling at the Company''s El Inca project, located approximately 4km northeast of the village of Inca de Oro. A total of 7 reverse circulation holes (1,633m) were completed, with two of these holes deepened by diamond drilling (470m). Propylitic alteration with only sub-anomalous Cu and Au geochemistry, possibly indicative of the margins of a porphyry system, was encountered in all holes under thick gravel. No further work is planned.

Qualified Person Notes

The mineral resource estimates contained in this news release have been prepared in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43-101"). The technical information in this news release, including the information that relates to geology, mineralization, drilling, and mineral resource estimates on the Berta deposit, is based on information prepared under the supervision of, or has been reviewed by Sergio Rivera, Vice President of Exploration, Coro Mining Corp, a geologist with more than 30 years of experience and a member of the Colegio de Geologos de Chile and of the Instituto de Ingenieros de Minas de Chile. The foregoing person is a "qualified person" for the purposes of NI 43-101 with respect to the geology, mineralization and drilling being reported on. The "qualified person" responsible for the independent resource estimate at Berta Sur was Sergio Alvarado Casas, a Consultant Geologist with more than 27 years of experience. He is General Manager and partner of Geoinvestments SpA and served as associated consultant for Propipe SA. He is a member of CIM, the Chilean Mining Commission, and the Instituto de Ingenieros de Minas de Chile. The technical information has been included herein with the consent and prior review of the above noted qualified persons. The qualified persons have verified the data disclosed, including sampling, analytical and test data underlying the information or opinions contained herein.

All mineral resources have been estimated in accordance with the definition standards on mineral resources and mineral reserves of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) referred to in National Instrument 43-101, commonly referred to as NI 43-101. U.S. reporting requirements for disclosure of mineral properties are governed by the United States Securities and Exchange Commission (SEC) Industry Guide 7. Canadian and Guide 7 standards are substantially different. This News Release uses the terms "measured," "indicated" and "inferred" resources. Mineral resources which are not mineral reserves do not have demonstrated economic viability. We advise investors that while those terms are recognized and required by Canadian regulations, the SEC does not recognize them. Inferred mineral resources are considered too speculative geologically to have economic considerations applied to them that enable them to be categorized as mineral reserves.


Alan Stephens, President and CEO

About Coro Mining Corp.:

The Company was founded with the goal of building a mining company focused on medium-sized base and precious metals deposits in Latin America. The Company intends to achieve this through the exploration for, and acquisition of, projects that can be developed and placed into production. Coro''s properties include the advanced San Jorge copper-gold project, in Argentina, and the Berta, El Desesperado, Payen, Chacay, Llancahue, and Celeste copper exploration properties located in Chile.

This news release includes certain "forward-looking statements" under applicable Canadian securities legislation. Such forward-looking statements or information, including but not limited to those with respect to the prices of copper, metallurgical results and resources, mining and processing costs involve known and unknown risks, uncertainties, and other factors which may cause the actual results, performance or achievements of the Company to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements or information. Such factors include, among others, the actual prices of copper, the factual results of current exploration, development and mining activities, changes in project parameters as plans continue to be evaluated, as well as those factors disclosed in the Company''s documents filed from time to time with the securities regulators in the Provinces of British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland and Labrador.

Coro Mining Corp.
Michael Philpot
Executive Vice-President
(604) 682 5546

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