Novo set for busy six months of Pilbara gold-antimony exploration

Novo Resources has given its high-grade Pilbara gold and gold-antimony prospects a solid nudge, including at Sherlock Crossing, where the company has defined a 1.5-kilometre-long soil antimony anomaly with coincident gold.

The antimony anomaly of better than 15 parts per million and up to 48.3ppm was identified in Novo’s extended sampling south of its initial grid around the historic Clarke Mine. Novo also identified a peak of 85 parts per billion (ppb) gold within the anomaly.

The distinctive, coherent, 200-metre-wide anomaly trends north-south within a strongly altered and sheared ultramafic unit, which outcrops intermittently over about 2.3km of strike, before being obscured by colluvial cover further south.

It appears to be coincident with the regional-scale Sherlock River Fault, although cover east of the fault has prevented further exploration in that direction. 

The company says its rock samples from the intensely sheared and altered ultramafic have come up with grades of up to 0.22 per cent antimony, without any significant quartz veining being noted.

Novo is planning to drill its Sherlock anomaly in the second half of the year. It will also undertake detailed mapping and sampling to get a better handle on the possible sources of the anomalism and the likelihood of it extending further south. 

Meanwhile, Novo has recently completed a reconnaissance air core drilling program at its near-coastal Balla Balla project, 75km southwest of Port Hedland.

The project straddles a 20km-long section of the regional scale Sholl Shear. Scout drilling is testing concepts in up to 10 separate target areas along the shear and its related splay faults under shallow cover. 

The regional-scale program entailed 187 air core holes for 5996m along fences of multiple holes set 640m to 2.8km apart. The hole depths range from 5m to 79m in variable cover between 5m and 35m deep and average 22m depth.

Sampling included 3m composites down the full length of the holes, which were assayed for gold by fire assay. This was supplemented by a bottom-of-hole sample from each hole, which was assayed for gold and 52 other elements by fire assay and four-acid digest. 

The work identified seven drill holes exhibiting intense sulphide mineralisation, quartz veining or strong alteration for multi-element analysis. The company  is awaiting results from two further holes.

Drilling was undertaken along about 5km of the Sholl Shear on six fences and along 4km of the Louden’s Fault on four fences centred around Babbage. A further two fences of holes were put in about 2km south of the Sholl Shear at Ramquarry, about 7km northeast of Babbage.

The program identified broad zones of low-level anomalism associated with the Sholl Shear, including two hits of better than 80ppb gold at Ramquarry. The best hit yielded 114ppb gold.

More anomalies were picked up in the bottom-of-hole samples and in the selected multielement assays, including 1m assaying 96.8 grams per tonne (g/t) silver and 8.1ppm antimony from 28m.

Another hole delivered 1m at 182ppm antimony and 6.72g/t silver at a 44m bottom. Novo is still waiting on multielement assay results for the entire hole. 

Multielement analyses for the full length of a second hole reveal anomalous bismuth, antimony and tellurium from 57m to 78m depth, with peak results of 71.6ppm bismuth, 47.3ppm antimony and 6.23ppm tellurium. 

Multielement analysis from the full length of a third hole shows anomalous molybdenum, antimony, gold and tellurium from 45m to 74m, peaking at 70ppb gold, 14.50ppm bismuth, 99.7ppm molybdenum, 11ppm antimony and 11.8ppm tellurium. 

Additionally, a fourth hole nailed 1m assaying 299ppm copper and 24.7ppm antimony from 43m in a bottom-of-hole sample. 

Finally, a fifth hole bored through 12m going 277ppm copper, 303ppm zinc and 11.5ppm antimony from 30m from the multielement suite down the full hole length. 

The top gold-silver-bismuth-antimony-copper-moly signatures are present at both Ramquarry and South Babbage, along the Sholl Shear.

The results are interpreted as being related to semi-massive pyrite mineralisation, strong silica-chlorite alteration and/or zones of intense quartz veining, which points to significant hydrothermal activity. 

Novo sees its peak silver values as being related to an interpreted fold axis in regional magnetics and one or more porphyritic mafic intrusion.   

The company also has a joint venture over the Egina prospect, in which Northern Star Resources is earning a 50 per cent interest. Northern Star recently finalised its acquisition of De Grey Mining and has begun assessing De Grey’s data to help plan future exploration at the Becher deposit and surrounding area. 

Novo entered into an earn-in and joint venture agreement with De Grey in June 2023 for the company’s Becher project and adjacent tenements within the Egina gold camp. 

Becher sits between the Wohler Faults and the Mallina Shear, about 30km west of Northern Star Resources’ recently-acquired Hemi gold deposit. Hemi is an intrusion-hosted style of gold mineralisation, new to the Pilbara region, with a scale not previously encountered in the Mallina Basin.    

Northern Star acquired Hemi from De Grey through a scheme of arrangement finalised on May 5. Hemi contains an estimated mineral resource of 13.6 million ounces and shows potential for mining by large-scale, low-strip-ratio, low-cost, open-pit mining.

Novo management says its Egina joint venture area covers a large and strategic land position in the prospective Mallina Basin. 

Importantly, the Egina gold project tenements are highly prospective for significant intrusion-related deposits and enclose ground with similar attributes to the nearby Hemi deposit.

De Grey exceeded a $7 million minimum expenditure commitment for Becher under the earn-in deal in September 2024. The company must spend a further $18 million by June 30, 2027, to earn a 50 per cent interest in Becher. At this time, an unincorporated joint venture will be established. 

Novo last year forged ahead with exploration of the Tabba Tabba shear corridor, which is part of the company’s Egina gold camp. First pass surface geochemistry and mapping are in progress in the central part of the corridor. 

Novo has recently prioritised obtaining access to the Teichman prospect on the Tabba Tabba Shear corridor within the Yandeyarra Aboriginal Reserve, where previous explorers picked up near one-ounce gold results from surface at several prospects over a 2.3km strike, including 25.5g/t and 32.3g/t gold from rock samples.

The company has been successful in obtaining approval to carry out low-impact exploration activities on parts of Novo’s tenements in the reserve. The proposed work will comprise up to 10 days of mapping and targeted rock sampling. Until now, only limited modern exploration has been undertaken in the reserve.

Novo Resources’ executive co-chairman and acting chief executive officer Mike Spreadborough said: “We have been methodical in our assessment of advanced gold and antimony targets over the first half of 2025, which has set Novo up for a busy second half of exploration. We have identified several compelling targets including the Sherlock Crossing prospect, where our highly experienced geological team has defined a 1.5km antimony anomaly, which will be a priority for drilling in the short term.” 

Spreadborough said a strengthening gold price and growing global interest in antimony would place Novo in an exciting position as the company executes its exploration plans and completes its drilling programs over the coming months. 

In the second half of last year, Novo completed a review of the antimony-gold potential across its Pilbara landholdings. 

As with Sherlock Crossing, Novo has highly ranked its Southeast Wyloo ground for its antimony potential. Southeast Wyloo includes two 2km-strike antimony+/-gold stream sediment anomalies, where reconnaissance rock chip sampling in mid-2023 yielded peak results of 387g/t silver, 2.4 per cent copper, 0.38 per cent antimony, 0.52g/t gold, 5 per cent lead and 1.6 per cent zinc. 

The company says it plans to complete mapping and rock chip sampling during the second half of the year, before planning a drilling program.

Novo has an extensive Pilbara landholding on its plate, graced by sample results which support well-based concepts across a variety of terrains in mostly virgin ground. The targets also feature favourable lithologies and giant structures, which have been known for years but remain seriously under-explored. It all points to a very busy six months coming up for the company.

Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au