Astral Resources (ASX:AAR) has increased its Theia deposit mineral resource estimate (MRE) by 22% for the Mandilla Gold Project, 70km south of Kalgoorlie in Western Australia.
The deposit is estimated to have 54 million tonnes (Mt) at 1 gram per tonne of gold for 1.74 million ounces (Moz) of contained gold. The deposit was previously calculated to have 42Mt at 1.1g/t gold for 1.43Moz of contained gold in April 2025.
The nearby Feysville deposit is predicted to have 5Mt @ 1.2g/t of gold for 196 kilo ounces (koz) of contained gold. The Spargoville deposit is believed to have 3Mt @ 1.4g/t of gold for 139koz of contained gold.
The entire Astral project area is estimated to have 62Mt @ 1.1g/t of gold for 2.07Moz of contained gold.
A 99-hole (11.1km) in-fill program within part of the Stage 1 Theia open pit found a maiden measured mineral resource of 1.3Mt @ 1.3g/t for 57koz of contained gold.
The updated Mandilla MRE will help to guide detailed mine design work to support the Mandilla Definitive Feasibility Study.
“Pleasingly, the MRE has also delivered a significant 22% increase in contained gold from 1.43Moz to 1.74Moz. When reported on a like-for-like basis with the April 2025 MRE using a $3,500 gold price and 0.39g/t lower cut-off, the updated MRE at the flagship Theia deposit still increased by 15%,” Managing Director Marc Ducler says.
“Notwithstanding the recent volatility in the gold price, the price is 100% higher than the design assumptions used in the June 2025 Prefeasibility Study. In this environment and given our confidence that the Theia deposit remains open at depth, we are now evaluating an underground mining option for Theia.”
Astral is now performing a six-hole (3km) diamond drilling program that will target up to 175m of vertical depth extension across several sections below the central Theia deposit.
The program aims to measure the Theia mineral system’s potential scale and define future growth potential.
“Work streams for the Definitive Feasibility Study and mining approvals continue to be advanced. Heritage clearance surveys are also currently in progress,” Ducler says.
“Pending completion of planned heritage clearance surveys at Spargoville and the broader Kamperman area, the Astral exploration team is also looking forward to getting a reverse circulation rig back into our highly prospective exploration portfolio of tenements in the near future.”
Astral Resources is a gold exploration company with assets mainly in Western Australia’s Kalgoorlie-Boulder region.
Write to Richard Szabo at Mining.com.au
Images: Astral Resources
