Arrow Minerals Ltd (ASX:AMD) has strengthened its geological understanding of the Yarraloola Copper Project in Western Australia’s Pilbara after locating and reviewing core from 7 historical diamond drill holes, including mineralised intersections that will help guide a planned 2026 drilling campaign.
The historical core is held at the Geological Survey of Western Australia (GSWA) Core Library and includes three holes containing mineralised intercepts. The standout result is from YD2, which returned 32.7 metres at 0.7% copper, 0.3% lead, 0.4% zinc and 16.3 g/t silver from 54 metres. The historical drilling was not analysed for gold.
Arrow said inspection of the core had also provided further support for Western Mining Corporation’s historical interpretation that Yarraloola may represent a volcanogenic massive sulphide (VMS) system.
Historical core sharpens exploration picture
The company located core from holes YD1, YD2, YD4, YD8, YDH11, YDH12 and YDH13, with mineralised intercepts recorded in YD1, YD2 and YD4. Arrow’s review concluded that historical geological logging and sampling for the mineralised holes was appropriate for the style of mineralisation encountered.
A more detailed section of YD2 between 76.2 and 84.43 metres returned a length-weighted 8.23 metres at 0.9% copper, 0.6% lead, 0.5% zinc and 25 g/t silver.
The interval comprises altered and metamorphosed mafic volcanic rocks containing disseminated and vein-associated sulphides, including pyrite, chalcopyrite and galena. GSWA has also photographed the core and completed HyLogger-4 spectral scanning, with Arrow now interpreting the data to better understand alteration associated with mineralisation.
Surface sampling provides an additional exploration angle, with rock-chip results of up to 0.95 g/t gold recorded adjacent to areas historically drilled for copper. Arrow intends to analyse future drilling for a broader suite of metals including gold.
Managing director David Flanagan said the preserved core would help Arrow correlate geology with geophysical anomalies and assays and improve its ability to identify alteration signatures during the upcoming drilling program.
Yarraloola drilling taking shape
Yarraloola is around 80 kilometres east of Onslow in Western Australia’s West Pilbara and contains historical copper workings that have received little modern systematic exploration for about 50 years. Previous drilling identified copper, silver, lead and zinc mineralisation within interbedded volcanic and sedimentary rocks.
Arrow acquired an 80% interest in the project, with the transaction completed in June 2026.
Working with geoscience consultancy Newexco, the company has prioritised the Fraser, Ava and Yarraloola Copper Mine targets for drilling later in 2026. Additional geophysical work is planned over the Mr Thomas and southern target areas, which are also considered prospective for copper and gold.
Field inspections have confirmed that reverse circulation drilling is suitable for testing the principal targets, while engagement with drill contractors, consultants and laboratories is underway.
The broader 2026 work program includes surveying historical drill collars, further non-destructive testing of the preserved core, geochemical and geophysical targeting and drilling at Ava, Fraser and Yarraloola, including holes designed to validate historical results and test new targets.
About Arrow Minerals
Arrow Minerals is advancing the Yarraloola Copper Project in Western Australia’s Pilbara.
At Yarraloola, the company is combining historical drilling and geological information with modern geophysics, geochemistry and planned RC drilling to assess copper, gold and polymetallic exploration targets. The historical dataset is being used primarily to support targeting, with Arrow noting that some older information does not meet the level of detail required under contemporary JORC reporting standards and will require validation through modern exploration.