Great Boulder’s belief that it has yet to uncover the full potential of its Mulga Bill prospect has been backed by drilling identifying a broad copper-silver zone.

Multi-element assays from recent diamond drilling and retrospective assays from earlier reverse circulation drilling highlighted a broad, tabular zone of copper and silver mineralisation adjacent to high-grade gold mineralisation already defined at the prospect within its Side Well project in Western Australia.

Notable results include 14.5m at 0.59% copper, 1.17 grams per tonne (g/t) gold and 10.74g/t silver from 189.5m (22MBDD001), 17m at 1.21% copper, 0.35g/t gold and 8.92g/t silver from 83m (21MBRC046), and 24m at 0.49% copper, 0.25g/t gold and 3.65g/t silver from 94m (21MBRCD093).

Great Boulder Resources (ASX:GBR) is now evaluating data and carrying out target planning for follow-up drilling of this copper zone.

Managing director Andrew Paterson noted that while the company had only just started retrospectively assaying RC samples after recognising the chalcopyrite-rich copper zone in its initial RC drilling last year, the results were exciting.

“This doesn’t change our focus on drilling high-grade gold intersections at Mulga Bill but it helps us understand the project’s full potential. There may be scope for recovering copper as part of a potential mining scenario,” he added.

“The fact that we see individual samples with copper as high as 3.44% and silver at 171.38g/t indicates this zone could host a significant amount of metal.”

Copper potential

The tabular, copper sulphide-rich zone contains disseminated chalcopyrite and pyrite, making it a visible feature in the 3D-IP and gravity data.

It is located on the eastern margin of the induced polarisation (IP) anomaly while the high-grade gold-only intersections are slightly further west.

Notably, the sulphide intersection in diamond hole 22MBDD001 sits within a 74.6m zone averaging 5.76 parts per million bismuth, which suggests that it is located within the centre of the alteration system.

Upcoming activity

Great Boulder is currently awaiting the remaining assays from its diamond drilling program and is drilling aircore holes with a focus on infilling the southern half of the Mulga Bill – Loaded Dog corridor at the Side Well Project.

The AC rig will then move to the Whiteheads Project north of Kalgoorlie later in the month to test several geochemical targets as well as some follow-up drilling from previous AC programs.

In late June, an RC rig is scheduled to mobilise to Side Well with drilling planned to continue for the rest of this year.



This article was developed in collaboration with Great Boulder Resources, a Stockhead advertiser at the time of publishing.


This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.