Argyle Diamond Mine

Useful Information

Location:	Kununurra, Kimberley region, far northeast of Western Australia. 550 km southwest of Darwin. (-16.716886, 128.397726)
Open:	closed. [2023]
Fee:	closed. [2023]
Classification:	Diamond Mine, Open Cast Mining
Light:	n/a
Dimension:	Ar=45 ha.
Guided tours:	D=4 h.
Photography:
Accessibility:
Bibliography:
Address:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info.

History

1890s	diamonds discovered in the Pilbara region.
1972	Kimberley region identified as being the most likely location for diamonds, joint venture formed.
1977	diamond-bearing kimberlite pipes discovered in Ellendale.
1979	deposit discovered by the Ashton joint venture.
1983	alluvial diamond mining.
1985	production of mine began.
2002	operated by the Argyle Diamond Mines Joint Venture, owned by Rio Tinto.
2005	preparation for underground mining by creating underground infrastructure like two underground crusher chambers and dewatering pumps.
2013	beginning of underground mining.
NOV-2020	mine closed.

Geology

Argyle was the first diamond orebody mined commercially which is not hosted in kimberlite. The AK1 pipe at Argyle instead consists of olivine lamproite. Diamonds in lamproite were new to the diamond world in the 1970s, and Argyle was the only economically viable lamproite diamond mine for many years.

The rocks of the Kimberley Plateau are nearly flat-lying sedimentary and volcanic rocks. Deposited between 1.6 and 1.9 billion years ago, those rocks originate from the Proterozoic, which is rather old. The basement consisting of crystalline igneous and metamorphic rocks is more than 2.5 billion years old, which is Archaean age.

The lamproite pipe was eroded over time, forming placer deposits nearby. Those relocated soft sediments containing diamonds were mined by so-called alluvial diamond mines. However, after they had been removed to a certain point the pipe was found below, and so the open pit mining of the pipe started.

Description

The Argyle Mine was the world’s largest single producer of diamonds. In 2013, it produced about 10.2 million carats of diamonds. It is located in a remote, rugged and hot desert, with temperatures of over 40 °C. Operated by 520 employees which were based at Perth, working two weeks 12-hour shifts at the mine and then spending two weeks at home.

The diamond-bearing rock was dislodged by drilling and blasting, then loaded by excavators into 120 tons dump trucks. At the processing plant the diamonds are extracted by physical processing techniques: crushing, scrubbing, screening and gravity separation. Finally, diamond recovery was achieved by the use of X-ray sorting machines. Diamonds fluoresce under X-ray and are thus easily identified by the sorter.

We generally list show mines, in other words, abandoned mines which are now tourist sites. This mine is an exception, it offered tours while it was still operating. There were several possibilities to visit this sight, but generally only in day trips from Kununurra, which included plane and/or coach ride. The four-hour mine tour included process plant, diamond viewing room, natural history museum, open-pit lookout, and buffet lunch at Argyle Village. It was possible to combine a flight over the Bungle Bungle Ranges with the mine trip. Unfortunately, the mine was closed in 2020, the last batch of blue diamonds was auctioned for a spectacular price, mining ceased, and most stops for the tour are currently rehabilitated. They are working together with the aboriginal owners of the land, to reshape and rehabilitate the land, preserve ecological and cultural heritage values, support future land uses and ensure a smooth transition for the local community. In other words, currently it’s still possible to see the open cast from the plane to the Bungle Bungles, but it will be gone soon. In other words, this was a show mine while it was operating, but is not any more, now after it was closed. And while Rio Tinto is beaming with joy at the good intentions of its rehabilitation work, we have a tear in our eye at the loss of such a great show mine.