Tolmer is located ~5km W of Tarcoola and ~130km SE of the Central Gawler Mill (Challenger), and is the site of Barton’s recent dual high-grade silver and gold discoveries in the ‘western silver zone’ and the ‘eastern gold zone’. The ‘western silver zone’ is notably silver dominant mineralisation.
Between 2020 and 2023 Barton defined a new regional structural model under ~15km of the historical Tarcoola Goldfield. Test drilling during 2024 identified high-grade gold at Tolmer with grades up to 83.6 g/t Au validating Barton’s thesis for a previously unrecognised structure.
Further sampling of Tolmer mineralisation also confirmed unusually high concentrations of silver, with grades of up to 312 g/t Ag associated with the highest grade gold mineralisation. While silver is a common accessory mineral in the Tarcoola Goldfield, it has historically been a minor accessory.
Subsequent follow-up drilling during late 2024 and 2025 then identified a second zone of mineralisation located ~500m to the west of the original Tolmer discovery. Drilling identified considerably higher silver grades of up to 17,600 g/t Ag, plus accessory gold of up to 51.2 g/t Au.
Multiple rounds of reverse circulation and diamond drilling have confirmed a ~1.5km wide mineral footprint, and soil geochemistry analyses confirm broad surface gold (Au), silver (Ag) and lead (Pb) anomalism across Tolmer, with potential for material extensions of Au-Ag-Pb mineralisation.
Tolmer Silver Project high grade drilling
Mineralisation
In the ‘western silver zone’ drilling has identified broad, silver dominant mineralisation largely independent of gold in a shallow horizon starting from near surface. This mineralisation ranges from 10 – 20m in thickness, grades approximately 100 g/t Ag, and is open to extensions to the west.
A second ‘lower horizon’ of mineralisation, near the interpreted boundary of oxide and fresh zones, hosts much higher grade silver and gold mineralisation in broad intervals with grades up to 17,600 g/t Ag and 51.2 g/t Au. This lower horizon appears open to extensions to the south and to the east.
Given the clear potential of this mineralisation to become a shallow, material economic contributor to Barton’s regional development strategy, we are systematically building up our understanding of this mineralisation and local structure to enable efficient follow up infill and extensional drilling.
