June 16 2015, Marimaca Copper Corp. (“Coro” or the “Company”) (TSX Symbol: COP) is pleased to announce the conclusions of an updated Preliminary Economic Assessment (the “Updated PEA”) for the Berta project, together with a combined US$9.0 million convertible debenture and equity financing package provided by Greenstone Resources L.P. (“Greenstone”). Berta is located in the III Region of Chile and is owned by SCM Berta (“SCMB”) a Chilean company whose shareholders upon closing of the financing will be Marimaca Copper(65%) and ProPipe SA (“ProPipe”) (35%), an engineering firm based in Santiago, Chile.

The Updated PEA has an after-tax NPV (8%) of US$35.2 million, and an IRR of 75%, using a base case copper price of US$2.80/lb. The Updated PEA envisages a phased start-up. Phase 1 involves the acquisition and remediation of the Nora SXEW plant and the trucking of high grade material from the Berta Sur deposit for 11 months. Phase 2 involves the installation of the Berta crusher, pads and site facilities; the expansion of the Nora plant to 5ktpy of cathode; and the installation of Pregnant Leach Solution (“PLS”) and water pipelines between Nora and Berta.

The ~US$9.0 million combined convertible debenture (US$6.5 million) and equity financing (~US$2.5 million) will provide US$7.15 million for the Phase 1 capital expenditures requirements at Berta and US$1.85 million in working capital for the Company. Marimaca Copperwill also offer existing shareholders and interested parties the opportunity to provide additional equity on the same price of C$0.04 per share, as agreed with Greenstone. An additional capital requirement of US$12.6 million will be required for the development of Phase 2 at Berta. Using a base case of US$2.80/lb copper, it is estimated that Berta will generate approximately US$5.9 million in cash flow before and during the Phase 2 development which would be available to fund the Phase 2 capital requirements. SCMB has had advanced discussions with vendors and construction companies and has identified approximately US$8.0 million in vendor and construction finance that may be available for Phase 2. SCMB will look to finalize these arrangements or seek alternative financing arrangements for Phase 2 upon completion of the Phase 1 financing.

Alan Stephens, President and CEO of Marimaca Coppercommented, “We are very pleased to have negotiated a combination equity and convertible financing package with Greenstone who we warmly welcome as a cornerstone investor in Marimaca Copper. This financing, which is subject to shareholder approval, and our revised development plan, will allow for the accelerated start-up of cathode copper production from Berta, which we now anticipate will be in October this year. The staged development of Berta is an example of our commitment to “bootstrapping” our projects to reduce risk. Our new major shareholder is also keen to see our Planta Prat and Marimaca projects brought to account as swiftly as possible, and we will be advancing both during the year. Greenstone’s investment in Marimaca Copperis a major vote of confidence in our projects and management team and we are confident that we are now on our way to achieving our objective of becoming a copper producer from a number of operations in Chile.”

Details of the Greenstone Financing
The financing is comprised of two elements; a US$6.5 million Convertible Debenture and a ~US$2.5 million equity private placement. The Company also confirms that it has elected not to pursue the previously announced Senior Secured Bridge Facility that was announced on March 18, 2015.

US$6.5 million Unsecured Convertible Debenture
The convertible debenture financing (the “Convertible Debenture”) is comprised of two tranches, being US$5.1 million (“Tranche 1”) and US$1.4 million (“Tranche 2”) repayable on the date that is 350 days after the drawdown of the respective tranches. In the event that the amounts are not repaid in full in cash, any unpaid amounts will be converted into common shares of Marimaca Copperat a conversion price of C$0.04 per share. Tranche 1 and Tranche 2 require repayments of US$6.375 million and US$1.75 million respectively, resulting in an effective interest rate of ~25%.

The structuring of the tranches is designed to facilitate the acquisition of the Nora Plant and required work programs (Tranche 1) with Tranche 2 being advanced after the lifting of a suspension order on the Nora Plant (the “Suspension Order”), which is discussed in more detail below. Due to the potential issuance of common shares upon conversion of the Convertible Debenture, the Company will be required to seek shareholder approval prior to draw down of Tranche 1. Shareholder approval will be sought at the Company’s upcoming Special and Annual General Meeting (“SAGM”), which is anticipated to be held on or about July 17, 2015

The following are the principal condition precedents (“CPs”) to each tranche:

The Suspension Order was issued by SERNAGEOMIN, the Chilean Mining Authority in 2014, and in order to be lifted requires some minor remediation work to be done as well as the filing of a closure plan and technical project report which have already been filed by SCMB on behalf of the previous owners. The Company anticipates that the remediation work program will take approximately one month to complete, with the lifting of the Suspension Order thereafter.

~US$2.5 million Equity Private Placement
Greenstone has also agreed to purchase up to 79,800,000 Marimaca Coppercommon shares at a price of CAD$0.04 per share by way of a private placement for total gross proceeds of CAD$3.192m (the “Private Placement”). The conditions precedent to completion of the Private Placement are identical to the condition precedents to Tranche 2 of the Convertible Debenture financing except that Greenstone may elect to waive satisfaction of all condition precedents and acquire up to 19.9% of the Company’s issued and outstanding common shares. In the event that Greenstone acquires its 79,800,000 common shares, it will own 33% of the issued and outstanding common shares of the Company.

In connection with the Private Placement, Marimaca Copperhas entered into an investor rights agreement (the “Investor Rights Agreement”) with Greenstone. The Investor Rights Agreement grants Greenstone the right to nominate one director of Marimaca Copperupon acquiring 10% of the outstanding common shares and a second director of Marimaca Copperupon acquiring 30% of the outstanding common shares. From and after the date which Greenstone holds 30% of the outstanding common shares of Coro, Marimaca Copperhas agreed that the board of directors will not exceed six directors. Accordingly, in the event the full Private Placement completes, two of the existing non-executive directors of Marimaca Copperwill resign. The Investor Rights Agreement also provides that from the date on which Greenstone (and for so long as) holds 10% of the outstanding Marimaca Coppercommon shares, Greenstone shall be granted a pre-emptive right to maintain its percentage ownership interest.

The Company also intends to offer existing shareholders and other interested parties the opportunity to purchase common shares at C$0.04 via a concurrent private placement.. Greenstone has the right to match any additional funds raised on a 1:3 basis to maintain their percentage ownership interest.

Conclusions of the Updated PEA Report for the Berta Project
The Updated PEA is an update of an engineering study completed by Geoinvestments released on September 14 2014. The Updated PEA includes a revised open pit mine plan, new operating and capital costs and financial analysis for the Berta project which contemplates the production of an average of 4,700ktpy of copper cathode for a period of 8 years. The Updated PEA was prepared in conjunction with the Berta resource estimate previously completed by Geoinvestments, as announced in the Company’s news release NR13-07 on August 7 2013, and which is available for review on SEDAR at www.sedar.com.

The table below sets out the revised mine plan and economics contemplated by the Updated PEA.

Table 1: Revised Mine Plan and Economics

(1) Includes closure costs and sustaining CAPEX not included in Phase 2
Geoinvestment’s assessments in the Updated PEA are preliminary in nature, mineral resources are not mineral reserves and do not have demonstrated economic viability, and there is no assurance the preliminary assessments will be realized. The outcome of the Updated PEA may be materially affected by the closing of the proposed financing with Greenstone, copper pricing, environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues. Inferred mineral resources are considered too speculative geologically to have economic considerations applied to them that enable them to be categorized as mineral reserves.

Mineral Resources
The resource estimate includes the Berta Sur deposit, and the Berta Central deposits which comprise five individual but adjacent deposits which have been subject to prior small scale open pit mining. In order to demonstrate the potential economic viability of the Berta Sur and Central resources, a series of pit optimizations using the Lersch & Grossmann algorithm was completed utilizing appropriate operating costs, results obtained from metallurgical test work, and a variety of copper prices. For a $3.00/lb copper price, the optimum pits were determined to contain 17.6mt at an average grade of 0.37%CuT and an overall stripping ratio of 0.49:1, as detailed in Table 2, below.

Table 2: In-Pit Resource Estimate based on $3.00/lb Cu, 0.1%CuT cutoff

Mining, Processing and Production Plan
The Berta project contemplates an open pit mine to extract oxide material from the Berta Sur and Central deposits using mining contractors, followed by crushing, agglomeration and heap leaching of higher grade (>0.3%CuT) material and dump leaching of lower grade (0.1-0.3%CuT) material. Overall material contained in the mine plan developed by Geoinvestments has 6.76mt of heap leach material, with an average grade of 0.56% CuT and 6.45mt of dump leach material (“ROM”) with an average grade of 0.20%CuT. A total of twelve 2m column tests have been completed on material from Berta Sur at Geomet SA and three 2m columns from Berta Central material at the Hydrometallurgy Laboratory of the University of Santiago de Chile, and this testwork was used to estimate recoveries of 78% of total copper for the heap leach and 45% of total copper for the ROM.

The updated mine plan assumes using a variable cut-off grade in year 1 of between 0.60% and 0.70%CuT, in order to maintain a constant feed to the Nora crusher for a period of 11 months, thus postponing part of the capital investment until year 2 of operations. A total of 0.4mt at 0.83%Cu will be mined and trucked to the Nora plant while 1.2mt of lower grade heap leach material and 0.6mt of ROM will be stockpiled for processing in year 2. In addition, the Nora plant will reprocess some spent ore stockpiles (“Ripios”) from the previous 2009-12 operation at a rate of ~30 tpm of copper cathode during Phase 1. The revised Berta mine plan and processing schedule are shown in Table 3 and Table 4 respectively, below;

Table 3: Berta Mine Plan

Table 4: Berta Processing Schedule

Due to the deferral of certain capital items, the revised mine plan results in the first eleven months of ROM material not being placed on pads and being separately stockpiled. This material may be re-handled in the future for further processing but is this is not considered in the current model.

Operating Costs
Operating cost estimates reflect the current market environment in northern Chile for contract mining, crushing, sulphuric acid, power supply, cathode production by SXEW, and transportation of PLS and water, and are shown on Table 5, below.
Major operating cost components are sulphuric acid (delivered) at US$94/t, and power at US$222/MWhr for Berta (generators) and US$117/MWhr for Nora (connected to grid).

Table 5: Life of Mine Operating Costs

Capital Costs
LOM capital costs are US$23.0 million which includes closure costs and option payments. The Company is adopting a phased build out of the project to utilize cash flow from the project and minimize financing costs. Phase 1 capital costs are US$7.15 million which includes the purchase of the existing Nora plant, remediation and refurbishment costs and initial start-up and working capital requirements. Phase 2 includes the installation of the Berta crusher, pads and site facilities; the expansion of the Nora plant to 5ktpy of cathode; and the installation of PLS and water pipelines between Nora and Berta.

Financial Analysis
The Berta project has been evaluated on both a pre-tax basis and after all Chilean taxes and a 1.5% royalty due to the Berta claim owner at a base case copper price of $2.80/lb and for sensitivity, at prices of $3.00/lb and $2.60/lb as shown on Table 6.

Table 6: Berta Economic Evaluation Summary

As noted elsewhere in this news release, Geoinvestment’s assessments in the Updated PEA are preliminary in nature, mineral resources are not mineral reserves and do not have demonstrated economic viability, and there is no assurance the preliminary assessments will be realized. The outcome of the Updated PEA may be materially affected by the closing of the proposed financing with Greenstone, copper pricing, environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues. Inferred mineral resources are considered too speculative geologically to have economic considerations applied to them that enable them to be categorized as mineral reserves.

Geoinvestments managed the preparation of the Updated PEA which will be completed and filed on SEDAR and Coro’s web site within 45 days of this release. All principal technical personnel and Qualified Persons (“QP”) participating in the development and review of the Updated PEA have extensive relevant experience.

The QP responsible for the independent resource estimate at Berta was Sergio Alvarado, a consultant geologist with more than 27 years of experience and general manager and partner of Geoinvestments. He is a member of CIM, the Chilean Mining Commission, and the Instituto de Ingenieros de Minas de Chile. 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, Marimaca Copper 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 and a QP. Jaime Simpson, a metallurgical engineer with more than 25 years of experience and employed by ProPipe as Development and Research Manager, was responsible for supervising the metallurgical test work and estimated the copper recoveries. Victor Araya, a civil mechanical engineer with over 15 years of experience in project development and management, and a board member of ProPipe and partner companies, was responsible for the engineering design and capital cost estimates. Oscar Rosas, a metallurgical engineer with more than 27 years of experience and General Manager of SCM Berta was responsible for the operating cost estimates and the financial analysis reported herein. Sergio Alvarado was responsible for the overall compilation of the Updated PEA, is the QP for purposes of National Instrument 43-101, and has approved the technical information contained in this news release. Alan Stephens FIMMM, President and CEO of Coro, a geologist with more than 39 years of industry experience is the QP for Marimaca Copperwho has reviewed and approved the contents of this News Release.

The technical information has been included herein with the consent and prior review of the above noted QPs, who have verified the data disclosed, including sampling, analytical and test data underlying the information or opinions contained herein.

All mineral resources in this news release 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. We advise investors that while those terms are recognized and required by Canadian regulations, the SEC does not recognize them. Mineral resources which are not mineral reserves do not have demonstrated economic viability.

About Greenstone
Greenstone is a private equity fund specializing in the mining and metals sector founded and run by former JP Morgan and Xstrata executives. The Greenstone team has over 80 years of experience in the sector covering all aspects of mining project development. Further details on Greenstone can be found at www.greenstoneresources.com.

About Coro
Coro’s strategy is to grow a mining business through the discovery, development and operation of “Marimaca Coppertype” deposits. These are defined as projects at whatever stage of development, that are well located with respect to infrastructure and water, which have low permitting risk, and which have the potential to achieve a short and cost effective timeline to production. Our preference is for open pit heap leach copper projects, where we will seek to minimise capital investment rather than maximise NPV, where we will prioritise profitability over production rate, and finally, where the likely capital cost is financeable relative to our market capitalization. Coro’s principal properties are the Berta pre-production project, the Planta Prat copper development project and the Marimaca copper exploration prospect, all located in Chile.

CORO MINING CORP.

“Alan Stephens”

Alan Stephens
President and CEO

For further information please visit the Company’s website at www.coromining.com or contact Michael Philpot, Executive Vice-President at (604) 682 5546 or [email protected]

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 completion of the Convertible Debenture and Private Placement financings with Greenstone (the “Greenstone Financings”), the concurrent private placement, the results and projections contained in the preliminary economic assessment of the viability of heap leach processing , including resource estimates, grade, the expected mine life, anticipated copper production, copper recovery, the commencement of construction, cash operating costs and other costs, capital costs, sensitivity to metal prices and other sensitivities. Forward-looking statements involve known and unknown risks, uncertainties and other factors which are beyond Coro’s ability to predict or control and may cause Coro’s actual results, performance or achievements to be materially different from any of its future results, performance or achievements expressed or implied by forward-looking statements. These risks, uncertainties and other factors include, but are not limited to, the risk that the conditions precedent to the Greenstone Financings and concurrent private placement, including approval of the Company’s shareholders, are not satisfied, copper price volatility, changes in debt and equity markets, the uncertainties involved in interpreting geological data, increases in costs, changes in project parameters as plans continue to be evaluated , environmental compliance and changes in environmental legislation and regulation, interest rate and exchange rate fluctuations, general economic conditions and other risks involved in the copper exploration and development industry, 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. Such forward-looking statements are also based on a number of assumptions which may prove to be incorrect, including, but not limited to, assumptions about the following: the satisfaction of the conditions precedent to completion of the Greenstone financings and the concurrent private placement; the availability of financing for exploration and development activities; the estimated timeline for the development of the Berta project; the supply and demand for, and the level and volatility of the price of, copper; the accuracy of resource estimates and the assumptions on which the resource estimates are based; the receipt of necessary permits; market competition; ongoing relations with employees and impacted communities; and general business and economic conditions. In addition, the preliminary economic assessment uses an estimated copper price of US$2.80/lb. The operating and capital costs in the preliminary economic assessment were developed to be reasonable estimates within industry benchmarks. There is no certainty that the results of the preliminary economic assessment will ever be realized. Should one or more of the risks or uncertainties involved in forward looking statements relating to the preliminary economic assessment materialize, or should the assumptions underlying the preliminary economic assessment prove incorrect, actual results of the preliminary economic assessment may vary materially from those anticipated, believed, estimated or expected. Accordingly, readers should not place undue reliance on forward-looking statements. Marimaca Copperundertakes no obligation to update publicly or otherwise revise any forward-looking statements contained herein whether as a result of new information or future events or otherwise, except as may be required by law.