Armstrong Ni Mine, Widgiemooltha, Coolgardie Shire, Western Australia, Australiai

Regional Level Types
Armstrong Ni Mine	Mine (Abandoned)
Widgiemooltha	Town
Coolgardie Shire	Shire
Western Australia	State
Australia	Country

30 km SW of Kambalda, originally worked by Titan Resources. The abandoned mine is west of the Coolgardie-Norseman Highway, half-way between Widgiemooltha and Spargoville.

The Armstrong nickel deposit was sold to Titan by Western Mining Corporation in September 2001, as part of Western Mining's exit strategy from nickel mining in the Kambalda region.

Titan began mining the deposit early 2004, however, something was seriously amiss from the testing results. Establishing an open cut mine is a large enterprise involving many people, much planning and a lot of money. You want to be certain the ore will be payable.

After removing 2.5 million bench cubic metres of waste from the open cut, Titan found its first two shipments of ore to WMC's Kambalda nickel concentrator rejected. The company refused to accept any further ore shipments, which were viewed as outside specifications in the purchase agreement. It was the result of partially oxidised material being mixed with the sulphide material, making the ratio of iron to magnesium oxide outside specifications. Only two months after the mine began, it closed. The board resigned en masse.

What was left was a closed mine, with an oxide resource opened, but largely not processed. With most mines in Western Australia, this material is usually processed before anyone has a chance to see if it contains rare species, or anything of interest.

In 2007, elsewhere in the region, at a place called Polar Bear Peninsula, David Vaughan was working as a prospector for a local company. He noticed a strange purple mineral, which was identified by the South Australian Museum as a new and unique species they called putnisite. It was IMA approved in 2012.

In 2012, local prospector, specimen miner, and mineral collector, Clive Daws was investigating the Armstrong Mine. With him were Ted Fowler and Alan Longbottom. They noticed a purple vein, which they thought might be stichtite or woodallite. It was subsequently identified as the second known occurrence of putnisite. The team recovered various other specimens from the mine in addition to putnisite including aragonite, millerite, calcite, dolomite, quartz needles, and dravite; some of them on the same specimens as the putnisite, along with an amorphous bluey-green Cr silicate material. Shortly after collecting, the bench collapsed, and the material is now buried under tonnes of earth, so no more specimens are available than those taken out in 2012.

Putnisite has a unique chemistry and structure unrelated to other minerals. It forms isolated pseudocubic translucent purple crystals in a matrix of quartz and near amorphous Cr silicate. It is chemically composed of strontium, calcium, sulphur, carbon, oxygen, and hydrogen. The species shows distinct pleochroism from pale purple to bluish grey. It forms in the oxidation zone of komatiite and dioritic lodes containing sulphide minerals. The species is named after Australian mineralogists Andrew and Christine Putnis.

Other Regions, Features and Areas containing this locality

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