Alto Metals Limited (ASX: AME) has highlighted significant potential for near-term resource growth in a targeting review of the historic Bull Oak gold mine and surrounding historic workings, located within the company’s 100% owned Sandstone Gold Project,
Extensional targets.
The style of mineralisation at the Bull Oak deposit is multiple stacked lodes hosted within a granodiorite (similar to that observed at Lord Nelson and Lord Henry). The intrusion has a strike length of approximately 500m and a width of up to 150m, with relatively steep dipping boundaries and has not been defined at depth. Importantly, gold mineralisation is not constrained by the boundary of the granodiorite and extends into the mafic rocks.
Two deeper historic holes drilled by WMC and Troy in 1985 and 2009, intersected multiple mineralised reefs with numerous instances of visible gold reported. The WMC diamond hole was only selectively assayed in mineralised zones, while the Troy hole returned 157m @ 0.5 g/t gold from 143m, incl. 1m @ 18.7 g/t gold from 297m (TRCD706)
Alto has drilled one RC hole at Bull Oak to date. SRC360 was drilled to test and validate the deeper historical results and intersected multiple stacked lodes in an overall intercept of 260m @ 0.41 g/t gold from 36m, which included high grade intercept of up to 14.3 g/t gold, with the hole ending in mineralisation.
The lack of recent exploration and untested mineralisation in significant intercepts, represents an exciting opportunity for Alto with significant potential to extend mineralisation below the shallow mined pit both up and down dip as well as along strike and at depth.
Key points identified so far from the review of Bull Oak and the surrounding historic workings include:
1. Based on the continuity of mineralisation observed at Bull Oak, there is considerable potential to define additional open-pitable gold resources at Bull Oak by extending mineralisation, both up and down dip of known mineralisation, as well as along strike and at depth.
2. The style of mineralisation at the Bull Oak deposit is multiple stacked lodes hosted within a granodiorite (similar to that observed at Lord Nelson and Lord Henry).
3. The intrusion has a strike length of approximately 500m and a width of up to 150m, with relatively steep dipping boundaries and has not been defined at depth. Importantly, mineralisation is not constrained by the boundary of the granodiorite and extends into the mafic rocks.
4. The current 65,000 oz gold resource captures the majority of the historical shallow results and is limited by the extent of drilling, as highlighted.
5. The Bull Oak open pit was last mined by Herald in 1997, when the gold price was ~US$320/oz, significant mineralisation remains immediately below the shallow open pit (mined to 60m depth).
6. Extensive workings over an area of approximately a 3km x 3km are relatively shallow (avg. 10m depth) and are considered a strong indication of the prospectivity of the wider area.
Mineralisation at Bull Oak is multiple stacked lodes hosted within a granodiorite, similar to that at Lord Nelson and Lord Henry. Most of the historic drilling at Bull Oak has been relatively shallow, however two historic holes drilled to 300m depth intersected multiple lodes and reported numerous instances of visible gold,” Managing Director, Matthew Bowles, said.
“A follow up deep hole drilled by Alto returned a wide zone 260m @ 0.4g/t gold from 36m, including 14.1 g/t gold and ended in mineralisation. The mineralisation is completely untested up and down dip of these intercepts, as well as at depth, and we are excited to have an RC rig arriving shortly to test these outstanding targets, that have the potential to drive near-term growth.”
