Resource growth at Brightstar’s Menzies gold project north of Kalgoorlie is looking increasingly likely after inaugural RC drilling returned numerous high-grade hits typical of the Menzies Goldfields.

The 37 hole drill program totalling 4,486m returned hits such as 1m grading 39.58 grams per tonne (g/t) gold from a down-hole depth of 56m (MGPRC020) and 4m at 3.11g/t gold from 48m (MGPRC023) at the Aspacia prospect and 8m at 4.09g/t gold from 138m including 1m at 16.57g/t gold from 143m in hole MGPRC009 at Lady Irene.

Brightstar Resources (ASX:BTR) noted that the assays indicate that high-grade historically mined underground mineralisation at Aspacia remains open both at depth and along strike while the geological theory for Lady Irene has been confirmed, opening up attractive targets for follow-up.

Assays are pending for a further 18 holes at Aspacia and the Lady Shenton-Lady Harriet “Link Zone”, which hosts the Westralia, South Dump and Golden Dicks brownfield targets.

“We are pleased to receive these assays from the Menzies Gold Project RC program, which tested and confirmed our understanding of the structural controls on the high-grade mineralisation,” managing director Alex Rovira said.

“This program has targeted areas of higher grades that have the potential to form possible ‘early-stage’ mining opportunities and for JORC mineral resource growth.

“The increased geological understanding from the Lady Irene program will allow us to refine drilling targets in the Northern Trend of our Menzies Gold Project, with several targets already identified for further investigation along the 7km of under-explored tenure, including our recently acquired tenement package from Ardea Resources Ltd.

He added that drilling also targeted high-grade ‘Menzies style’ mineralisation under the Aspacia headframe around the historical underground mine and the three targets at the Lady Shenton-Lady Harriet “Link Zone” that have the potential to host shallow oxide material.


Early, small-scale mining potential

Drilling at Lady Irene was designed to test for shallow mineralisation in and around the existing resource of 100,000t at 1.7g/t gold, or 6,000oz of contained gold, to determine if the potential for small-scale, early-stage mining and toll treating, similar to the upcoming Selkirk mining campaign is present.

The drill holes encountered a highly sheared mafic-ultramafic contact with variable
quartz veining within and along the shear, which is a different mineralisation style to the deposits near and south of Menzies.

Brightstar noted that the presence of an identified magnetic footwall unit may facilitate the use of geophysical techniques under shallow transported cover to refine targets along the roughly 7km long ‘Northern Trend’ of the Menzies Shear Zone.

Assays indicate that the mineralised system is not closed off at depth and presents a shallow southerly plunging target for potential further drilling campaigns, which is at least indicative that another Selkirk-style mining opportunity might be on the cards.


Potential for high-grade gold lode repetition

Meanwhile, historical records suggest that Aspacia production was modest in size but very high grade with more than 10,000oz of gold produced at a head grade of 35.7g/t.

Previous operator Intermin (ASX:IRC) noted that all three holes drilled in 2016 intercepted significant mineralisation, suggesting a strong structural component to the mineralisation along with a historical 2.5m intercept grading 113.32g/t gold.

Further compilation and interpretation of 3D drill and mine survey data has confirmed that several mineralised horizons exist.

This indicates that the gold intersections from Brightstar’s recent RC drilling at Aspacia are typical of “Menzies High Grade” gold mineralisation, which occurs as narrow, shear-hosted lenses within the Menzies Shear Zone.

The Aspacia Mine is known to have several lodes that have been offset at various locations by east-west striking faults along with a pegmatite fault.

Structural measurements suggest that the direction of movement on faults at Aspacia and other mines in the Menzies district is north block west or south block down, which effectively step the lodes to the west, thus representing attractive targets for lode repetitions with mineralisation also open at depth.


The road ahead

Looking ahead, the company’s geology team will use its increased geological understanding to carry out further exploration for gold along the 7km length of the Menzies Shear Zone between Lady Irene and Selkirk along with greenfields exploration in the recently acquired Ardea tenements.

Resource definition planning and drilling will also be carried out across the Menzies and Laverton gold project areas.

Brightstar also continues to undertake project development activities with a focus on delivering near-term production through the Selkirk joint venture and continuing the Scoping Study investigating the potential to monetise its +1Moz resource base at Menzies and Laverton.



This article was developed in collaboration with Brightstar Resources, a Stockhead advertiser at the time of publishing.


This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.