• A diamond rig has arrived at Side Well to commence drilling at Ironbark
• The diamond rig brings the total number of rigs on site to three
• Additional holes are being planned at Eaglehawk in response to the intersection of coarse visible gold

Great Boulder Resources ('Great Boulder' or the 'Company') (ASX: GBR) is pleased to provide an update on progress at the Company's flagship Side Well Gold Project ('Side Well') near Meekatharra in Western Australia. A diamond rig has arrived at Side Well to commence drilling at Ironbark, bringing the total number of rigs on site to three. The diamond rig will complete geotechnical and metallurgical holes at Ironbark, with a program of deep holes at Mulga Bill and Eaglehawk planned for Q4 2025. Additionally, the Company is planning additional holes at Eaglehawk in response to the intersection of coarse visible gold in hole 25EHRC024 announced on 9 September 2025. Assays are pending on 34 completed RC holes and 91 completed AC holes. With the recent uptick in gold exploration in WA, average sample turnaround time has slowed somewhat, with GBR assay turnaround currently averaging approximately 28 days compared to the long-term average of 21 days. Ongoing drilling will be planned as results are received, including any last holes required for resource definition at Eaglehawk, Ironbark and Side Well South.

The Company is planning a series of deep diamond holes into Mulga Bill and Eaglehawk during the fourth quarter of this year. With so much activity in the field, shareholders can expect a strong flow of news and exploration updates in the months ahead.