Kunwarara

Mining of magnesite began at the Kunwarara mine in Queensland in 1991 at the KG1 open pit that also contains the beneficiation plant. The KG 3 open pit came on-line eight years later, in 1999 and the following year, 2000, the KG2 open pit also began production. The Oldman South and Oldman North deposits were developed in later years. In 2000 a second pre-concentration plant was was constructed at the KG2 open pit. This concentration plant involved the crushing, scrubbing and screening of the magnesite. The two beneficiation plants treat the low silica, low calcium magnesite before it is trucked to the company's processing plant at Parkhurst. By the end of 2006 the Kunwarara operation had mined 43 million tonnes of ore that in turn had produced more than 5.7 million tonnes of top grade beneficiated magnesite.

Magnesite Discovered at Kunwarara in 1985
The magnesite deposit at the Kunwarara Mine was discovered in 1985 by Queensland Metals Corporation (QMC) and its potential to produce top grade refractory magnesia was quickly recognised. Pancontinental Mining Limited (Pancon) tool an early 40 percent interest in the venture and Radex Heraklith, an Austrian company, purchased ten percent.

Kunwarara Produces First Magnesite in 1991
The Kunwarara Project was given the go ahead in 1990 and its first production of magnesite occurred in November 1991. QMC acquired 10 percent of Radex's shares in 1994 and Pancon was purchased by Goldfields Limited in 1995. A series of other changes took place that eventually saw Australian Magnesium Corporation (AMC) finish up with 100 percent ownership. However, AMC was to sell the mine to Resource Capital Funds (RCF) in December 2004 and renamed the holding company operating the mine and controlling the magnesia and magnesite assets, to QMAG Limited.

Sebelco Acquires Kunwarara in 2012
World wide industrial and minerals company, Sibelco, which is based in Belgium, purchased 100 percent of QMAG Limited off RCF in April 2012. This acquisition underlined Sibelco's long term view of the market and put it in a stronger position to meets the future needs of its customers. Sibelco began its Australian operations in 2000 when it acquired Commercial Minerals, ACI Industrial Minerals and David Mitchell.

Kunwarara Mining Carried out in Conventional Open pit Manner
Mining operations at Kunwarara are carried out in the conventional open pit manner, the pits have an average from two to four meter depth of clay and soil overburden. Most pits are from 15 to 18 metres deep. The pits are developed sequentially to allow product quality to be balanced, they usually contain between 300 to 500 million tonnes of run-of-mine (ROM) ore.

Following the overburden being stripped the magnesite is mined on three metre benches but before this takes place the area is first drilled to determine details regarding the grade distribution of the magnesite below the surface.
Gravels, clays and matrix sands that comprise the reject material discharged from the beneficiation plant, along with magnesite and dolomite fines, are either trucked, or pumped, to pits that are mined out and re-deposited as tailings. This material settles and compacts quite readily after which it is rehabilitated with top soil and seeded.
†