Marimaca Copper Extends Ultra-High-Grade Bornite Zone at Pampa Medina

Exceptional Bornite Grades Highlighted in SPRD-05

Marimaca Copper Corp. (ASX:MC2) has unveiled compelling assay results from its ongoing 2026 drilling campaign at the Pampa Medina deposit in Chile. The standout intercept from drillhole SPRD-05 includes 16 metres grading 5.70% copper and 62.6 grams per tonne silver, with an ultra-high-grade 4-metre section hitting 11.32% copper and 144 g/t silver. This sits within a broader 96-metre sulphide interval averaging 1.19% copper and 11.7 g/t silver starting at 692 metres depth, underscoring one of the most robust bornite-mineralised mantos encountered at the project to date.

Continuity Across Central Zone Reinforces Deposit Scale

Drilling spaced on 150-metre centres continues to demonstrate strong lateral continuity of high-grade sulphide mantos dominated by bornite and chalcocite mineralisation. The sediment-hosted system extends across the initially defined 3km by 1.5km area of interest (AOI), with SPRD-05 drilled east of previously released hole SPRD-06 and approximately 650 metres northwest of SMRD-13, which also intersected the ultra-high-grade bornite zone. Another hole, SPRD-04, drilled 150 metres north of SMRD-13, returned broad mineralisation including 22 metres at 1.97% copper and 9.2 g/t silver from 610 metres.

Near-Surface Oxide Zones and Broader Exploration Efforts

Beyond the sulphide zones, near-surface oxide mineralisation was encountered north of the historic Pampa oxide footprint, with intervals such as 22 metres at 0.40% copper and 1.9 g/t silver from 60 metres depth. Marimaca is also advancing geochemical and geophysical programs across the broader Sierra Medina land package, focusing on Sierra Norte and Pampa Norte. Recent completion of audio-magnetotelluric (AMT) grids aims to identify extensions of mineralised sedimentary units within the interpreted sedimentary basin, with results pending.

Management Confident in District-Scale Potential

Sergio Rivera, VP Exploration, emphasised the significance of the results, noting that the continuity of high-grade copper and silver mineralisation across multiple stacked horizons provides confidence in Pampa Medina’s district-scale potential. The company plans to complete its 150-metre spaced delineation drilling campaign before compiling a maiden Mineral Resource Estimate (MRE), which will serve as a baseline for further step-out drilling targeting northern and western extensions.

Geological Setting and Deposit Model

Pampa Medina is a manto-style copper deposit hosted primarily in Jurassic-Triassic sedimentary units overlain by andesitic volcanics. The mineralisation transitions from near-surface oxides dominated by atacamite and chrysocolla to deeper sulphides including bornite, chalcopyrite, covellite, and chalcocite. Elevated silver grades correlate with copper mineralisation throughout. The deposit is affected by a complex structural setting including dyke swarms and normal faulting, which has been integrated into an updated geological model guiding the current drilling strategy.