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Follow-Up Work on Sulphide Discovery Hole MAD-22 Identifies Project’s First Anomalous Gold and Silver, Rigs Mobilized to Commence Drilling Sulphide Target

Exploration Programs

News Release

Follow-Up Work on Sulphide Discovery Hole MAD-22 Identifies Project’s First Anomalous

Gold and Silver, Rigs Mobilized to Commence Drilling Sulphide Target

Vancouver, British Columbia, February 15, 202 3 – Marimaca Copper Corp. (“Marimaca Copper” or the “Company”)

(TSX: MARI) is pleased to announce the results of assays for gold and silver from hole MAD-22 and to outline the first phase of

follow-up drilling of the exciting new sulphide target identified in diamond drill hole MAD-22, which intersected 120m at 1.7%

CuT including 92m at 2.11% CuT ( refer to announcement dated 15 December 2022). The anomalous gold and silver

encountered towards the end of MAD-22 is the first anomalous precious metal content encountered at the Marimaca Project

(“Marimaca” or “the Project”).

Highlights

• First anomalous gold and silver identified at Marimaca coincident with higher grades of primary copper mineralization in

MAD-22

o 100m of anomalous gold (majority >0.02g/t) and silver (majority >1g/t) from 140m

o 40m with an average grade of 3.74% CuT and 0.07g/t Au and 7g/t Ag from 186m

▪ Represents 40m with an average grade of 3.84% CuEq1 from 186m

• MAD-22 intersected over 240m of continuous mineralization from surface with a high grade primary mineral zone at

depth including:

o Reconfirms strong association of high-grade chalcopyrite with high magnetic susceptibility

o Encountered massive chalcopyrite over an interval of 92m with an average copper grade of 2.11% CuT from 140m

o Located immediately adjacent to the eastern wall of the whittle pit limits for the October 2022 MRE, indicating

potential for high grade, open pit-able mineralization

o Indications are that mineralization relates to a second, later stage, mineralizing event when compared to the broader

Marimaca Oxide Project

• Large scale magnetic anomaly previously identified believed to be prospective for mineralization similar to the primary

zone in MAD-22

• Five-hole diamond drilling program planned, and rig mobilised, to follow up results of MAD-22:

o 50m to 100m step outs from MAD-22

o First phase tests approximately 300m of strike potential around MAD-22 with a target width of up to 300m

o Drilling will test deeper extensions below the limit of drill hole MAD-22, which terminated in mineralization

o Second phase of up to five holes based on results of first phase increase tested strike length to 500m+

• Fully funded to test the exciting sulphide target

Sergio Rivera, VP Exploration of Marimaca Copper, commented:

“MAD-22 was a spectacular drill hole in terms of grade , continuity and the shallow nature of mineralization, and provided us

with valuable information with respect to potential sulphide feeder zones for the Project. As we have noted in previous releases,

there is a strong correlation between magnetic anomalism and the presence of primary copper mineralization. MAD -22 once

again strongly confirmed the relationship. It has also been noted that outcropping zones with higher prevalence of magnetite,

in veins and stringers, could be a good surface vector for future e xploration targeting Marimaca-style IOCG (Iron Oxide Copper

Gold) deposits.

1 CuEq is calculated using gold price of US$1,850/oz, silver price of US$22.50/oz and copper price of US$4.0/lb

“In 2020, we completed high resolution magnetic work and developed a 3D model which highlight s a large-scale magnetic

anomaly, which we estimate to be over 175 million 3 meters in volume, or approximately 475 million2 tonnes of high magnetic

susceptibility rock mass. MAD-22 was drilled into the southern extent of this anomaly, which extends over strike of approximately

1.0km and to a depth of around 800m below surface.

“The result of M AD-22 is an exciting confirmation of our view that there is significant sulphide potential below the MOD. We

have mobilized a rig to complete an initial follow up program to test the immediate 300m to 500m of strike around MAD -22.

Based on the results we achieve we will then plan an expanded programme.”

Overview

Following extensive drilling and geophysical work, the Company developed an exploration model which was based on a strong

correlation between higher grade chalcopyrite mineralization a nd high magnetic susceptibility, which was used to vector for

future deeper drilling campaigns. During the 2021 campaign, the deeper drilling, which was targeting deeper sulphide potential,

encountered additional oxide and secondary sulphides in a zone now known as MAMIX (refer to announcement dated 5 May

2021). This extended the envelope of leachable copper minerals by, in some cases, several hundred meters. This discovery was

a core component of the upgraded Mineral Resource Estimate (“MRE ”) released in Oc tober 2022 ( refer to announcement

dated 13 October 2022), but left the sulphide potential unaddressed.

A review of historical drilling data highlighted numerous broad zones of, typically remnant, primary mineralization, especially

around the centre of the project, which were identified but never properly followed up on due the focus on the MAMIX Zone.

Notable intersections were identified along section N7.435.800, with at least six drill holes enc ountering remnant primary

copper mineralization over a width of approximately 300m, east-west, across strike. There was a notable increase in magnetic

susceptibility as the sulphide zones were entered, although it should be noted that most of the drilling on N7.435.800 was not

directly coincident with the magnetic anomaly, but rather was on the periphery of it.

2 Based on average specific gravity of 2.75g/cm3

Figure 1: Section N7.435.800 with Significant Sulphide Intersections and Magnetic Anomaly

MAD-22 was drilled on section N7,435,550, which is located 250m to the south of N7 ,435,800 (figure 1) and intersected very

high-grade primary copper mineralization , which is not interpreted to be remnant in nature . In contrast to the drill holes on

N7.435.800, MAD-22 was drilled directly into an area with some of the highest magnetic susceptibilities encountered at the

project. As noted in the release in December 2022, MAD -22 encountered very high grades of primary copper mineralization

over broad downhole widths. MAD-22 noted similar mineral textures of magnetite veins and stringers and massive chalcopyrite.

Notably, MAD-22 was collared further to the east than all of the drilling on the northern section, and was drilled in the opposite

orientation. It is thought that the higher grade, primary (non remnant) mineralization on section N 7,435,800 should be further

to the east of drill holes MAR-125 and ATR-82 as noted in Figure 1.

Figure 2: Cross Section N 7,435,550 with MAD-22 Drill Hole

Borehole Teleview analysis of MAD-22 indicates that the structures controlling high-grade primary mineralization are oriented

north-north-east dipping at 75 to 80 degrees to the east. This is in contrast to the general structural sense of the Marimaca

Oxide Deposit, where dominant structures are oriented more n orth south and are more shallow dipping to the east. The

importance of dacitic dykes and the north-west trending regional faults and structures is also noted for the confluence of these

important geological features and their proximity to higher grade mineralization, both in the oxide and primary mineral zones.

Furthermore, it appears that the mineralization in MAD -22 is related to a second, later stage, mineralizing event. This could

explain the anomalous levels of precious metals, which have as yet been u nobserved in drilling and exploration work for the

Marimaca Oxide Project to date.

Follow Up Drilling Plan

The Company plans to step out drill an area covering approximately 500m of strike potential immediately around MAD -22

including Section N7.435.800 in the north, where the previous high grade remnant chalcopyrite intersections were noted. The

target zone is a pproximately 300m in width, east to west, across this area. Given the scale of the magnetic anomaly, the

Company believes there is potential for significant depth extensions, but for the initial program, 300m drill holes are plann ed,

which will extend the depth of MAD-22 by approximately 60m.

Drilling will be completed in two phases, with the second phase final design being based on the results from phase 1 and the

Company is fully funded to deliver both phases based on current work programmes.

Figure 3: Planned Drill Hole Locations of Phase 1 and 2 Sulphide Follow-up

Geophysics

In July 2020, Marimaca released the results from an initial drone mounted high resolution magnetic survey covering the

Marimaca Project (refer to announcement on 14th July 2020). The results showed a large scale magnetic anomaly immediately

adjacent and downdip of the Marimaca Oxide Deposit (“MOD”), within the same geometry as the interpreted downdip

extensions of the key controlling structures for the MOD. Based on the 3-D magnetic model created, it was estimated that the

magnetic anomaly had a volume of approximately 175 million cubic meters, which is equivalent to approximately 475 million

tonnes assuming a specific gravity of 2.75g/cm3.

Figure 4: Marimaca Large Scale Magnetic Anomaly with >0.1% CuT Outline

In parallel with this work, the Company completed a full review of all drill samples across the project to identify any relationships

with magnetic susceptibility and mineralization potential. A clear relationship exists between magnetism and the presence of

chalcopyrite was noted across the full drilling database of nearly 100,000m.

A review of MAD-22 showed this relationship clearly, with an increasing trend of magnetic susceptibility more generally when

moving into the primary mineralization zone, and strong spikes of magnetic susceptibility with the highest grades of copper

encountered in the drill hole.

Figure 5: Relationship of Magnetic Susceptibility and Drilling Across the Project

Table 1. Summary of Anomalous Precious Metal Intervals

Hole Depth (m) From (m) To (m) Intersection

(m) % CuT Au (g/t) Ag (g/t)

MAD-22 300

0 240 240 1.01% n/a n/a

Including 140 240 100 1.95% 0.05 6

Including 182 226 44 3.44% 0.07 7

Including 186 224 40 3.74% 0.07 7

Table 2. Drill Collars and Survey

Hole Easting Northing Elevation (m) Azimuth Inclination Depth (m)

MAD-22 375143.8 7435536.2 1,124.9 85 -55 240

Sampling and Assay Protocol

True widths cannot be determined with the information available at this time. DDH holes were sampled on a 2m continuous

basis, halved by a conventional core splitter on site with one half sent to the Andes Analytical Assay preparation laboratory in

Calama and the pulps then sent to the same company laboratory in Santiago for assaying. Samples were prepared using the

following standard protocol: drying; crushing all sample to -1/4” and passing through a secondary crusher to better than 80%

passing -10#; homogenizing; splitting; pulverizing a 400-600g subsample to 95% passing -150#; and a 125g split of this sent for

assaying. All samples were assayed for %CuT (total copper); %CuS (acid soluble copper) and Ag AAS. Au was Fire Assayed. A full

QA/QC program, involving insertion of appropriate blank s, standards and duplicates was employed with acceptable results.

Pulps and sample rejects are stored by Marimaca Copper for future

Qualified Person

The technical information in this news release, including the information that relates to geology, drilling and mineralization was

prepared under the supervision of, or has been reviewed by Sergio Rivera, VP of Exploration, Marimaca Copper Corp, a geologist

with more than 35 years of experience and a member of the Colegio de Geólogos de Chile, Instituto de Ingenieros de Minas de

Chile and of the Society of Economic Geologist USA, and who is the Qualified Person for the purposes of NI 43-101 responsible

for the design and execution of the drilling program.

The QP confirms he has visited the project area, has reviewed relevant project information, is responsible for the information

contained in this news release, and consents to its publication.

Contact Information

For further information please visit www.marimaca.com or contact:

Tavistock

+44 (0) 207 920 3150

Emily Moss / Adam Baynes

[email protected]

Forward Looking Statements

This news release includes certain “forward-looking statements” under applicable Canadian securities legislation. There can be

no assurance that such statements will prove to be accurate, and actual results and future events could differ materially fro m

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

Marimaca Copper, 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: risks related to share price and market conditions, the inherent risks involved in the mining,

exploration and development of mineral properties, the uncertainties involved in interpreting drilling results and other

geological data, fluctuating metal prices, the possibility of project delays or cost overruns or unanticipated excessive operating

costs and expenses, uncertainties related to the necessity of financing, the availability of and costs of financing needed in the

future as well as those factors disclosed in the annual information form of the Company dated March 2 8, 2022, the final short

form base prospectus and other filings made by the Company with the Canadian securities regulatory authorities (which may

be viewed at www.sedar.com). Accordingly, readers should not place undue reliance on forward-looking statements. Marimaca

Copper 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.

Neither the Toronto Stock Exchange nor the Investment Industry Regulatory Organization of Canada accepts responsibility for

the adequacy or accuracy of this release.