Marimaca Copper Corp. (TSX: MARI) is pleased to announce further results from the 2022 infill and extensional drilling campaign at the Marimaca Oxide Deposit. Results reflect a total of 6,130m across 31 drill holes.

The drilling intersected mineralization in-line with the current geological interpretation of the MOD. Drilling in the south-east zone of the MOD, on trend with the Sierra and Sorpresa satellite targets, continues to demonstrate extensions to green-oxide rich mineralization beyond the previously interpreted limits of the 2019 Mineral Resource Estimate (“MRE”). Copper oxide mineralization also remains open to the east of the MOD. Hole MAR-158 was drilled on a ~150m step-out from the eastern pit limits and intersected continuations of shallow green oxide mineralization. Drilling on the western boundary of the MOD confirmed limits of copper oxide mineralization with lower-grade intersections of thinning mineralization. In the central MOD, hole MAR-65Ext intersected extensions of higher-grade mineralization into the MAMIX zone.

Highlights

• Infill drilling intersected extensions to known green-oxide mineralization in the south-east zone of the MOD, consistent with previous 2022 results (see release dated March 28, 2022)
• MAMIX drilling intersected extensions to higher grade oxide and mixed mineralization at depth, improving confidence in the higher-grade core of the MOD and MAMIX
• Oxide intersections from step-out drilling on the north-eastern boundary of the MOD (MAR-158) demonstrates a material broadening of the MOD’s oxide halo to the east which is consistent with previous step-out drilling (MAR-126, see release dated May 5, 2021)
• Notable intersections include
  • MAR-65Ext intersected 332m at 0.44% CuT from 36m, including a higher-grade extension of 78m at 0.90% CuT from 218m
  • LAR-96 intersected 98m at 0.41% CuT from surface including 22m at 1.14% CuT from surface
  • MAR-172 intersected 200m at 0.25% CuT from 12m including 66m at 0.51% CuT from 38m
  • MAR-171 intersected 164m at 0.37% CuT from 2m including 96m at 0.53% CuT from 70m
  • MAR-158 intersected 72m at 0.36% CuT from 120m
  • LAR-03 intersected 346m at 0.32% CuT from 2m including 40m at 0.34% CuT from 272m
  • LAR-25 intersected 340m at 0.33% CuT from 12m
• The 2022 drilling program is now finalized with 38,570m of RC and 3,000m of diamond drilling complete
  • 21,992m of remaining drilling to be released pending final assay results

Sergio Rivera, VP Exploration of Marimaca Copper, commented:

“We have now completed the 2022 Marimaca drilling campaign with our work now focused on the upcoming mineral resource update planned for late September or early October.

“Overall, the 2022 program was a success. All our objectives going into the program were met and results continue to be in-line with our geological interpretation at the MOD, with the consistency of the Marimaca mineralization demonstrated again in this latest batch of results.”

Overview of Drilling Campaign Objectives

Marimaca’s 2022 RC drilling campaign consists of over 38,570m of drilling between the MOD infill and the MAMIX zone, the depth extension of the MOD.

Geological interpretation and resource modelling is currently underway ahead of the planned 2022 Mineral Resource Update (“MRE”) expected in late Q3. The 2022 MRE will capture drilling data completed up to June 30th, 2022, with the balance of the infill drilling (targeting conversion to Measured and Indicated Resource categories) to be captured in a subsequent MRE planned for early 2023.

Figure 1: Plan View of Infill Drilling Results, Pending Holes and MOD PEA Pit Shell:

https://www.globenewswire.com/NewsRoom/AttachmentNg/5a93e53e-c466-4d72-aabd-fcf039cca3cb

Table 1. Summary of Infill Drill Results

Table 2. Summary of MAMIX Drill Results

Table 3. Infill collars and survey

Table 4. MAMIX collars and survey

Sampling and Assay Protocol

True widths cannot be determined with the information available at this time. RC holes were sampled on a 2m continuous basis, with dry samples riffle split on site and one quarter sent to the Andes Analytical Assay preparation laboratory in Calama and the pulps then sent to the same company laboratory in Santiago for assaying. A second quarter was stored on site for reference. Samples were prepared using the following standard protocol: drying; crushing to better than 85% passing -10#; homogenizing; splitting; pulverizing a 500-700g subsample to 95% passing -150#; and a 125g split of this sent for assaying. All samples were assayed for %CuT (total copper) and %CuS (acid soluble copper) by AAS. A full QA/QC program, involving insertion of appropriate blanks, standards and duplicates was employed with acceptable results. Pulps and sample rejects are stored by Marimaca Copper for future reference.

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 Paola Kovacic, Exploration Manager, Marimaca Copper Corp, a geologist with more than 20 years of experience and a member of the Colegio de Geólogos 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 she 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.