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MARI.TO ·

Coro Reports a Significantly Increased Resource Estimate for the Marimaca Claim

Resource Estimates

Suite 1280 – 625 Howe St

Vancouver, B.C. V6C 2T6

News Release

TSX: COP

www.coromining.com

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Coro Reports a Significantly Increased Resource Estimate

for the Marimaca Claim

April 12, 2018 - Coro Mining Corp. (“Coro” or the “Company”) (TSX Symbol: COP) is pleased to announce a

significantly increased resource estimate for its Marimaca claim, located 22 kilometres east of the port of

Mejillones in the II Region of Chile, (Fig. 1). The updated resource estimate will be used to inform the feasibility

study that Coro is completing as part of its earn in requirement to acquire a 75% interest in the Marimaca claim,

and in turn inform the strategic review of the group asset portfolio.

Highlights

 Contained copper tonnes (CuT) in the measured and indicated categories increased 103% to 303,698

tonnes compared to previous January 2017 resource estimate.

 Excellent conversion of resources to higher confidence categories as a result of infill drilling.

 Updated resources do not include potential upside results from drilling completed earlier this year on

the neighbouring La Atomica claim, nor from holes drilled elsewhere on the Marimaca claim.

 Feasibility study covering the Marimaca claim due for completion in coming weeks

Commenting on the announcement, Luis Tondo, President & CEO of Coro said: “I’m delighted to report that the

updated measured and indicated resource estimate for the Marimaca claim has more than doubled to over

300,000 tonnes of copper. The work completed so far will enable us to move ahead with the feasibility study,

which we anticipate completing in the coming weeks. Even at this early stage, the results at the Marimaca claim

have been encouraging and exceeded our expectations. Consequently, we look forward to restarting our drilling

program once we have finalised the consolidation of the Marimaca district announced earlier this year, confident

that there is more upside potential to be proven still.”

Resource Estimate

The resource estimate was completed by a third-party, NCL Ingeniería y Construcción at a variety of cut-off

grades and the resources at a 0.20% CuT cut-off grade, presented in the following table:

Category

tonnes

%CuT %CuS

Cu tonnes

x 1000 CuT CuS

Measured 22,407 0.70 0.49 156,398 108,672

Indicated 24,347 0.61 0.39 147,300 95,197

Measured + Indicated 46,754 0.65 0.44 303,698 203,869

Inferred 11,043 0.48 0.28 52,894 30,367

CuT: total copper tonnes

CuS: acid soluble copper tonnes

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In Pit Resource

To demonstrate the potential economic viability of the Marimaca claim resource, a series of Whittle pit

optimizations was completed utilizing appropriate operating costs, results obtained from metallurgical test work,

and a variety of copper prices. The resources were estimated only for oxide and mixed-enriched copper

mineralization which can be processed by heap leaching (HL) and run of mine (ROM) leaching to produce cathode

copper. Due to their differing metallurgical characteristics, the resources were categorised according to mineral

type. No resources were estimated for primary sulphide mineralization, occurring in deeper portions of the

deposit. At a $3.50/lb long term copper price, the in pit resource was estimated to be:

Category tonnes %CuT %CuS Cu tonnes

x 1000 CuT CuS

Measured

Brochantite 11,009 0.85 0.62 93,469 68,147

Chrysocolla 6,240 0.61 0.47 38,252 29,391

Wad 2,919 0.31 0.18 9,048 5,342

Mixed-Enriched 1,288 0.99 0.33 12,700 4,199

Total 21,456 0.72 0.50 153,469 107,079

Indicated

Brochantite 10,044 0.81 0.54 81,457 54,639

Chrysocolla 6,077 0.53 0.40 32,209 24,491

Wad 4,230 0.30 0.18 12,776 7,403

Mixed-Enriched 1,204 0.88 0.32 10,582 3,889

Total 21,555 0.64 0.42 137,023 90,422

Measured & Indicated

Brochantite 21,053 0.83 0.58 174,925 122,787

Chrysocolla 12,317 0.57 0.44 70,461 53,882

Wad 7,149 0.31 0.18 21,824 12,745

Mixed-Enriched 2,492 0.93 0.32 23,282 8,088

Total 43,012 0.68 0.46 290,492 197,501

Inferred

Brochantite 2,134 0.72 0.40 15,406 8,557

Chrysocolla 2,664 0.53 0.35 14,174 9,405

Wad 698 0.27 0.15 1,878 1,054

Mixed-Enriched 189 0.70 0.37 1,315 691

Total 5,685 0.58 0.35 32,773 19,706

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As with the 2017 resource estimate, the in pit resource is constrained by the Marimaca property limits, such that

all blocks occurring outside the property were assigned a 0%CuT grade. Accordingly, the pit contains 68,271kt

of waste and has a strip ratio of 1.4:1.

Parameters Used in the Estimation of the Mineral Resource

The mineral resource estimate was prepared in accordance with NI 43-101 and was based on a total of 27,606

meters of drilling in 129 holes, including 113 holes, 23,548 meters of reverse circulation drilling and 16 holes,

4,058 meters of diamond drill drilling. The mineral resource estimate has been generated from drill hole assay

results and the interpretation of a geologic model which relates to the spatial distribution of copper in the

deposit. Four leachable copper mineralization types were identified during geological mapping and drill hole

logging, namely; brochantite, chrysocolla, and copper wad dominant oxides; and mixed oxides & sulphide,

including enriched material. Resources were estimated for each mineralization type. Grades were capped

according to the following criteria:

Mineral Type %CuT %CuS

Capped at Capped at

Brochantite 8 5.1

Chrysocolla 4 2.5

Wad 1.6 1.6

Mix-Enrich 7 1.8

Grade estimates were made using ordinary kriging with nominal block size measuring 5 meters long, 5 meters

wide and 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 the following technical and economic parameters:

Item Cost Unit

Mining cost $2.80 US$/t

HL Process Cost including G&A $11.30 US$/t

ROM Process Cost including G&A $4.90 US$/t

Selling Cost $0.07 US$/lb

Heap Leach Recovery 75%

ROM Recovery 37%

Copper Price $3.50 US$/lb

Based on geotechnical studies completed to date, the pit slope varies from 44-46o.

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Qualified Persons

The mineral resource estimates contained in this news 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, drilling and

mineralization of the Marimaca claim, was prepared under the supervision of, or has been reviewed by Sergio

Rivera, Vice President of Exploration, Coro Mining Corp, a geologist with more than 36 years of experience and

a member of the Colegio de Geologos de Chile and of the Institute of Mining Engineers of Chile, and who is the

Qualified Person for the purposes of NI 43-101 responsible for the design and execution of the drilling program.

The independent Qualified Person responsible for the resource estimate at Marimaca is Luis Oviedo Hannig, a

geologist with more than 41 years of experience at NCL Ingeniería y Construcción S.A. He is a member of the

Colegio de Geologos de Chile and the Institute of Mining Engineers of Chile and registered with the Qualification

Commission of Resources and Mining Reserves (CRISCO, CMC, Membership Number 013), and with a

postgraduate degree in "Certification and Validation of Mining Assets” from Queens University and PUVC.

Alan Stephens, FIMMM, Executive Director of Coro Mining Corp, a geologist with more than 43 years of

experience, and a Qualified Person for the purposes of NI 43-101, is responsible for the contents of this news

release.

Figure 1: Location of Marimaca

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Figure 2: Final Pit Boundary - showing drill holes used in estimate in red and cross section in green

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Figure 3: Cross Section Through Block Model - looking to NE

For further information please contact of visit www.coromining.com or contact:

Nicholas Bias, VP Corporate Development & Investor Relations

(604) 682 5546 x 202 or +44 (0)7771 450 679 | [email protected]

Email us at [email protected]

Follow us on Twitter @coromining

This news release includes certain "forward-looking statements" under applicable Canadian

securities legislation.Forward-looking statements in this press release relate to, among other

things completion of a feasibility study for the Marimaca claim. Statements concerning

mineral resource estimates may also be deemed to constitute forward-looking information to

the extent that they involve estimates of the mineralization that will be encountered if the

Maricunga claim is developed. Actual future results may differ materially. There can be no

assurance that such statements will prove to be accurate, and actual results and future events

could differ materially from those anticipated in such statements. Forward-looking

statements reflect the beliefs, opinions and projections on the date the statements are made

and are based upon a number of assumptions and estimates that, while considered

reasonable by Coro, are inherently subject to significant business, economic, competitive,

political and social uncertainties and contingencies. Many factors, both known and unknown,

could cause actual results, performance or achievements to be materially different from the

results, performance or achievements that are or may be expressed or implied by such

forward-looking statements and the parties have made assumptions and estimates based on

or related to many of these factors. Such factors include, without limitation: the occurrence of

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unexpected financial obligations, fluctuations in the price of commodities; fluctuations in the

currency markets; changes in national and local government, legislation, taxation, controls,

regulations and political or economic developments; risks and hazards associated with the

business of mineral exploration, development and mining (including environmental hazards,

industrial accidents, unusual or unexpected formations, pressures, cave-ins and flooding); the

presence of laws and regulations that may impose restrictions on mining and employee

relations 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.

Accordingly, readers should not place undue reliance on forward-looking statements. Coro undertakes 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.