Arrow Minerals (ASX:AMD) has located core from seven historical diamond holes drilled at its Yarraloola Copper Project in Western Australia about 50 years ago, providing new geological data ahead of drilling planned for later this year.
The Geological Survey of Western Australia (GSWA) has preserved core from holes YD1, YD2, YD4, YD8, YDH11, YDH12, and YDH13 at its Core Library in Perth.
Three of the holes contain mineralised intercepts, led by 32.7m @ 0.70% copper (Cu), 0.30% lead (Pb), 16.3 grams per tonne silver (Ag), and 0.40% zinc (Zn) from 54m in YD2. The historical drilling was not assayed for gold.
Arrow says its inspection supports Western Mining’s historical interpretation that Yarraloola may host a volcanogenic massive sulphide system. The company also considers the original geological logging and sampling appropriate for the mineralisation encountered.
Managing Director David Flanagan says access to the preserved core will help Arrow interpret its geophysical and assay data before drilling.
“The knowledge acquired from the historical drill core makes a big difference, and we are grateful for the diligence shown by GSWA in preserving the core,” Flanagan says.
“It doesn’t just help us correlate geology to the various geophysical anomalies and assays; it improves our ability to identify important and subtle alteration signatures in the upcoming 2026 drill program.”
GSWA has photographed the core and scanned it using its HyLogger-4 system, which maps minerals through their spectral signatures. Arrow says it is also seeking approval to undertake further non-destructive testing to examine the alteration associated with mineralisation and assess the potential for gold within pyrite.
The mineralised sections cannot be resampled because previous work reduced them to quarter core, the minimum amount GSWA requires to remain preserved.
Surface sampling beside the historical copper drilling has returned up to 0.95g/t gold. Arrow says it plans to analyse its future drilling for a broader suite of metals, including gold.
The company also notes it is preparing reverse circulation drilling at the Yarraloola mine area and the Ava and Fraser targets following further geophysical work and analysis of the historical core.
Arrow acquired an 80% interest in Yarraloola in June. The project lies about 80km east of Onslow in Western Australia’s Pilbara region.
Write to France Pinzon at Mining.com.au
Images: Arrow Minerals
