Great Boulder to apply “secret sauce” technique on Castle ground

Great Boulder Resources says surface geochemistry techniques undertaken on Castle Minerals Polelle gold project near Meekatharra as part of a farm in deal has unearthed several exciting pathfinder anomalies. Castle previously picked up 3000 auger samples and 1000 soil samples at the project and subsequent independent analysis by Great Boulder consultants has likened the geochemistry at Polelle to Great Boulder’s Mulga Well and Ironbark deposits.

Great Boulder is exploring Polelle under an agreement with Castle Minerals which gives it an option to acquire 75 per cent of the project.

The Mulga Well and Ironbark deposits lie within Great Boulder’s Side Well project, about 25km to the north/north-east of Polelle.

Mulga Well and Ironbark boast a combined indicated and inferred resource of 7.45 million tonnes at a grade of 2.8g/t gold for 668,000 ounces of gold in both open-pittable and underground locations.

The targeting techniques we have used successfully at Side Well have highlighted some exciting targets with the same pathfinder geochemistry as our Mulga Bill and Ironbark deposits. The coincidence of geochemical anomalism over a structural feeder zone is an exciting target and we are looking forward to drilling it. We think our experience at Side Well has given us the secret sauce for finding gold around Meekatharra, so it will be exciting to test those theories in a new area.

The Polelle and Side Well project areas are linked by a major structural synclinal axis, while the most significant 4km long zone of Mulga Bill style of gold-silver bismuth-copper-molybdenum-tungsten anomalism in Polelle is also defined as a distinct trend along the Albury Heath shear within Polelle.

The style also occurs in other targets about 7km to the north-west of the main anomaly.

Great Boulder says its work along the Ironbark corridor at Side Well has refined its geochemical targeting, using combined assays for gold with silver, bismuth, copper, molybdenum and tungsten to target intrusive-related Mulga Bill-style gold mineralisation.

It is also employing gold-arsenic-antimony to target orogenic Ironbark-style gold mineralisation.

The model appears to have been validated by initial drilling at the Saltbush prospect in the southern part of the Side Well project, which intersected 9m going 5.20g/t gold from 15m in the second reverse circulation (RC) hole in the same mafic-ultramafic lithological setting as Ironbark – and directly northwards along strike from Polelle.

Great Boulder says that while the 4km long geochemically anomalous zone in Polelle shares the same geochemistry as that seen at Mulga Bill and Ironbark, few targets in the area have been properly tested.

However, Great Boulder says the geochemical targeting methods it employed in its Side Well project achieved considerable success using the same pathfinder element suite as those which characterise its two deposits.

The company says it is planning a limited air-core (AC) drilling program within areas which acquired heritage clearances completed by Castle in 2022.

Castle undertook a heritage survey over priority target areas on the eastern side of Polelle in preparation for an air-core (AC) drilling program in 2022 but with Castle’s strategic focus shifting to its Kambale graphite project in Ghana, the planned drilling was never completed.

Great Boulder says it has also lodged a heritage clearance request with the local traditional owners to clear access to other parts of the Polelle ground.

Ongoing work will include field reconnaissance and mapping over Polelle to assess its suitability for auger sampling drilling and Great Boulder intends to extend the area of auger work to infill gaps in current coverage.

Is your ASX-listed company doing something interesting? Contact: matt.birney@wanews.com.au