Alto Metals Ltd (ASX:AME) has leads on a series of high-grade gold extensions thanks to a first-pass drill program at the Sandstone Gold Project’s historical Oroya Mine in WA.
The precious metal explorer covered 2,000 metres — the first drilling activity at Oroya in 15 years — and intersected up to 37 g/t gold above historical workings, confirming mineralisation extends northwest of the mine’s open pit.
What’s more, the wide-spaced step-out campaign has validated Alto’s targeting model and confirmed remnant mineralisation exists in unmined areas of the old workings.
An update to Sandstone’s open-pittable 635,000-ounce, 1.6 g/t gold resource is slated for release this quarter.
The results are in
Some of the highlights from Alto’s first-pass shallow drilling program include:
- 3 metres at 13.8 g/t gold from 65 metres, including 1-metre at 37.1 g/t from 66 metres;
- 6 metres at 1.3 g/t from 41 metres, including 1-metre at 5.5 g/t from 41 metres;
- 3 metres at 2.8 g/t from 104 metres, including 1-metre at 7.6 g/t from 104 metres;
- 1-metre at 5.4 g/t from 113 metres; and
- 5 metres at 1.1 g/t from 126 metres, including 1-metre at 3.4 g/t from 128 metres.
While it’s still early days, the findings confirm the Sandstone Main Reef’s northwest extension is a priority target area.
As such, Alto is already putting pen to paper and plotting a round of follow-up drilling to find high-grade gold.
The company is also interested in some historical unmined results, which increase Oroya’s scale potential:
- 23 metres at 6.2 g/t gold from 87 metres, including 2 metres at 55.9 g/t from 89 metres;
- 8 metres at 17.9 g/t from 69 metres, including 1-metre at 137 g/t from 73 metres;
- 9 metres at 14.6 g/t from 42 metres, including 1-metre at 120 g/t from 42 metres;
- 6 metres at 8.3 g/t from 49 metres, including 2 metres at 23.2 g/t from 51 metres; and
- 13 metres at 3.1 g/t from 22 metres, including 2 metres at 11.9 g/t from 28 metres.
Between 1904 and 1920, the Oroya mine generated 220,000 ounces at 16.5 g/t gold and in its open pit heyday (1994 to 1995), the mine produced around 25,000 ounces at 2.3 g/t.
“Outstanding high-grade gold target”
Alto managing director Matthew Bowles said: “This is the first time the historic Oroya Mine has seen any drilling in over 15 years and we are pleased the results have successfully confirmed extensions of the reef, both to the northwest beyond the north end of the pit, and down dip to the west, validating our targeting model.
“We are excited to see gold mineralisation in a number of holes from this initial wide-spaced drill program, demonstrating the reef remains mineralised and we look forward to commencing a follow-up drill program in the coming weeks.
“While our focus firmly remains on growing our 635,000-ounce shallow gold resource, with an updated mineral resource coming this quarter, Oroya is an outstanding high-grade gold target within our Sandstone Gold Project.”