Vertex Minerals (ASX: VTX) is advancing gold processing at its Hill End project in New South Wales by integrating TOMRA Mining’s advanced LASER ore sorting technology. This strategic move enhances operational efficiency and aligns with Vertex’s commitment to environmentally sustainable mining practices.
Located about 200 km northwest of Sydney, between Bathurst and Mudgee, the Hill End project encompasses a significant portion of the historic Hill End goldfield. This region, part of the Eastern Lachlan Fold Belt, has historically yielded over 1.6 million ounces of gold and is renowned for producing large gold nuggets, including the famous Holtermann Nugget.
The project’s geology features gold mineralization associated with quartz veins within the Chesleigh Formation and Crudine Group. These characteristics make the ore amenable to gravity separation techniques, allowing for high recovery rates without the use of chemicals.
The Hill End goldfield is also the site of the discovery of the Holtermann Nugget, the largest single mass of gold ever found. Unearthed in 1872 at the Star of Hope Mine, this specimen weighed approximately 285 kilograms and contained an estimated 93 kilograms of gold. Although commonly referred to as a nugget, it was a gold-bearing quartz specimen. This monumental find brought international attention to the region and remains a significant part of Australia’s gold mining heritage.
Roger Jackson, executive chairperson at Vertex Minerals, explained: “The reason why this site is so historically significant is that it was one of the first places where the gold rush started. They found this incredible deposit of high-grade gold, very significant for the Australian mining industry. Vertex decided to open up this mine because it was already permitted, it was a high-grade gold mine, and we could see an opportunity to have one of the best high-grade gold mines in Australia.”
Gavin Rech, area sales and technical manager Australia at TOMRA Mining, said: “What excites me about this project is to work with a team like Vertex and this beautiful historic site, and mine in a more efficient and intelligent way.”
In pursuit of enhancing ore processing efficiency and reducing environmental impact, Vertex Minerals has incorporated TOMRA Mining’s LASER ore sorting technology into its processing workflow. This sensor-based technology enables precise separation of ore from waste rock, improving feed grade and reducing the volume of material processed downstream.
The integration of LASER sorting complements the existing gravity-based processing plant, which includes crushing, ball milling, and concentration equipment. By pre-concentrating ore before it reaches the mill, Vertex achieves higher throughput and lower energy consumption.
To evaluate the suitability of the Reward Gold Mine’s ore for sensor-based sorting, Vertex transported 160 kilograms of material to TOMRA’s test facility in Sydney. The test work involved screening the sample to a 20–60mm size fraction and processing it through TOMRA’s LASER sorter, which targets quartz-rich particles associated with gold.
Rech explained: “The tests’ findings indicate a 337% increase in gold grade and a 79% reduction in mass, with minimal gold loss, demonstrating the technology’s effectiveness in upgrading ore prior to processing,”
Roger Jackson added: “We can mine bigger stopes and then sort it all and still get the same gold back through the process plant,”
Vertex’s adoption of TOMRA’s LASER technology aligns with the company’s vision of producing “green gold.” By enhancing ore quality before processing, Vertex reduces the need for chemical treatments and minimizes tailings. The coarse liberation size of the gold also requires less energy for crushing and grinding, further decreasing the environmental footprint. Gavin Rech adds, “The material discarded by the sorter is proper barren material that we can use as road base or aggregate and dispose of responsibly.”
Jackson continued: “The TOMRA ore sorter has been a game-changer for this site. We have reduced power, water and time we’ve got to run the plant because it’s so efficient in sorting out the waste from the gold ore.
By utilizing TOMRA’s LASER sorting technology, Vertex Minerals aims to boost gold production and uphold sustainable practices. The company is seeking additional innovations to enhance operations and minimize environmental impact.
Rech concluded: “It’s important that TOMRA is part of the industry change we’re seeing, with companies like Vertex stepping in to take an old traditional system and mine it in a more efficient way, with low energy, zero chemicals, no tailings dam. That’s something TOMRA definitely wants to be a part of.”
For further information about TOMRA, visit www.Tomra.com.
