Meeka commissions Murchison plant ahead of first gold in late June

Meeka Metals has kicked off its much-anticipated plant commissioning, navigating a decisive moment when ore is first fed into the plant, paving the way for first gold from its gravity circuit later this month. 

Meeka’s commissioning team is onsite at the company’s Murchison project, 50 kilometres north of Meekatharra in Western Australia, working with the construction and processing crews to ensure everything is fault-free and at or coming up to specification. 

The initial “dry” phase of commissioning has passed evaluation, in which all electrics and plumbing were brought online and tested for connectivity and load.  Valve settings were also adjusted to ensure adequate, leak-free process water supply to and circuit-water balance within the plant at start-up. 

With full functionality assured, the next “wet” commissioning phase has been launched which includes first ore being fed into the processing plant.

The added ore will bring the Meeka’s new ball mill up to its design running load. All other systems, including conveyors, pumps, water loads, hydro-cyclones, dewatering screens and other gear, will be checked off as doing their jobs without running dry, choking or overflowing. 

Importantly, the leach tanks take some time to reach proper pulp density as the initial feed from the ball mill arrives and the agitators come under load to keep the pulp solids in suspension. Pulp chemistry in the tanks will also be constantly measured for gold grade, pH, lime and cyanide concentrations.   

After sufficient time in the leach circuit, fine gold is won from the leach pulp through the magic of activated carbon, carbon stripping and an electro-winning system. 

At the far downstream end, tailings flow to the storage facility will be monitored for density to minimise water loss and - importantly - for gold and potentially other valuable metals, to ensure the correct recovery levels are maintained and that  nothing valuable is lost.

As the tails dam fills up and the fines settle, clean water on top of the tailings can be skimmed off and returned to process water. All those pumps, dewatering systems and lines also need to be monitored and tweaked as necessary.

The gravity circuit will be the first place anyone will see physical gold in the plant. It is designed to capture coarse gold before it ends up in the leach tanks, where it would settle out and/or consume cyanide unnecessarily. 

Meeka’s ore zones contain significant high-grade primary and secondary gold in the shallow oxide ore zones. The gravity circuit is designed to catch coarse components of this gold early, after which the gold room will turn it into the company’s first doré gold bars.

Meeka Metals managing director Tim Davidson said: “With commissioning of processing in June 2025, we achieve an important milestone for the Murchison project as we transition from developer to producer status. We are now focussed on maximising expanded open pit mining following the success we are having with the drill bit. Additionally, first ore is expected from our first underground mine at Andy Well in the September 2025 quarter.”

Semi-refined doré bars typically contain gold and silver, and often minor quantities of metals such as copper, produced as a final or by-product of mining or smelting. 

The exact composition of doré bars depends on the operation and the early stages of the refining process. They require further refining to reach a high-purity state. 

Doré bars are not considered bullion but rather a partially refined form of gold, which is often sent to refineries such as the Perth Mint for further processing. 

Whatever Meeka’s Murchison bars are refined to, it’s a safe bet dozens of fingers will be crossed and eyes focused on what all the expense, time, effort, blood, sweat and tears delivers later this month.   

Meeka has slated its first gold pour from gravity gold in late June, followed shortly afterwards by first gold sales and cash flow early next month.

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