Aus Tin Mining Archives - International Mining

There are changes afoot at Aus Tin Mining’s Taronga Stage 1 project, in Australia, after the ASX-listed company appointed a contractor for an initial program of mining, crushing and civil works, and made the decision to acquire its own crushing plant.

The company said it had appointed Townes Contracting, a firm with experience in quarrying and crushing operations, to undertake the initial mining, crushing and civil works associated with Taronga Stage 1. Expected to last three months, this contract should provide for site establishment, initial mining of some 50,000 t of ore and waste, crushing of ore and construction of a water dam, Aus Tin said.

Aus Tin’s decision to acquire its own crushing plant, meanwhile, follows a crushing trial completed with a preferred contractor in May. Aus Tin explained: “The company was unable to secure their services in a timeframe consistent with operational requirements.”

The Taronga tin project is the world’s fifth largest undeveloped tin reserve, based on a JORC resource of 57,200 t of contained tin, plus 26,400 t of contained copper and 4.4 Moz of silver, Aus Tin says.

The company completed a prefeasibility study in 2014 that outlined a project treating 2.5 Mt/y of ore, producing an average 2,800 t/y of contained tin over nine years. Following this, in 2015, the company commenced the approvals process to undertake trial mining and pilot processing of 340,000 t of ore to evaluate several areas of potential upside. This project – Taronga Stage 1 – is now fully permitted.

Peter Williams, CEO of Aus Tin, said: “Now that we are no longer constrained in any way by contractors at Granville, we have decided to take a different approach to the operation and believe this will provide the optimal means to exploit this small, but high grade tin deposit.”

Back in March, Aus Tin Mining commenced owner mining at the Granville East tin mine in Australia, just over a week after liquidators were named to its previously appointed mining contractors, Jemrok Pty Ltd.

Aus Tin said the initial programme of work to be carried out by Townes Contracting will provide “several important outcomes”. Included within this is a provisional metal reconciliation, with the average grade of ore mined compared with the respective mining blocks estimated in the 2014 probable reserve; productivity and cost data to optimise pricing for the remainder of Stage 1, and; material for additional metallurgical test work planned prior to the commencement of Stage 1 pilot plant operations.

The remainder of the Stage 1 project, including the expanded mine and pilot plant operations are expected to commence in late 2019.

In terms of the crusher Aus Tin is due to acquire, the company said it had made an initial payment on a second-hand mobile crushing plant, located in Tasmania, and refurbishment of the unit – expected to take three to four weeks – had commenced.

“The key benefits of owner crushing will be a lower operating cost and ability to crush ore on an ongoing basis rather than the campaign basis required for contractors,” Aus Tin said.

Aus Tin Mining says tin mining has commenced at its Granville East mine in Tasmania, Australia.

Run of mine material from the first mining block – estimated to total some 430 t – will be transported to the processing plant enabling plant feed to transition from low‐grade stockpiles to high‐grade mine material, Aus Tin said.

The first mining block is located at the southern end of the open pit and was extracted from the hangingwall shale that overlies the cassiterite-magnetite skarn, Aus Tin said.

Assay results from blasthole samples collected for grade control purposes have confirmed the high‐grade mineralisation at Granville East, Aus Tin said. These included intersections of 4 m at 6.56% Sn and 4 m at 4.34% Sn.

Aus Tin CEO, Peter Williams, said: “We are delighted to have achieved this major milestone as we transition to Level 2 operations and will now move to processing this material. We are particularly delighted with the grade of the first block, which across eight holes averaged 2.1% Sn and is more typical of underground mines.”

Aus Tin said it has been seeking to directly procure certain services contracted to its civil and mining contractor.

“To minimise further delays to the operations, the company has now assumed additional components of the contract, including blasting services and fuel supply,” Aus Tin said. “Furthermore, the company has removed the crushing component of the contract and is currently in discussions with alternative parties as well as examining capacity for utilising surplus equipment at the processing plant.”

Aus Tin shipped its first tin concentrate from Granville back in 2017, and has been working on developing a “Level 2” operation at East Granville at the same time.

Aus Tin chooses different tack at Taronga Stage 1 project

Aus Tin kicks off Granville East mining with high-grade block