North east larsons

The North East-Larsons satellite mining operation is part of the Girilambone Mine that includes the Hartmans and Murrawombie mines. All have substantial copper deposits below their oxide pits. These mines are considered part of the Straits Resources Limited larger Tritton Mining Operation near Nyngan in New South Wales.

Successful Exploratory Drilling Showed the North East-Larsons Mining Operation Could go Underground
The ensuring development and studies of the larger Tritton Mine deposit have indicated similar ore structures could well occur at the satellite deposits as does occur at the Tritton Mine. To determine if this was in fact the case resource extension drilling began in 2006 focusing on the sulphide ore bodies that existed below these open oxide pits. The exploratory drilling proved to be successful and a decision was made to support the construction of an underground decline at North East-Larsons mines along with a plant upgrade. Work on the decline began in the latter part of 2007, at the same time as throughput capacity was increased at the ore processing plant from one million tonnes a year to 1.4 million tonnes. However, the Global Financial Crisis (GFC) hit the mining industry pretty hard in 2008 and all work on the decline was suspended.

Plans Began in 2010 to Prepare for a Post GFC Future for the North East-Larsons Mine
When 2010 came around most mining companies were looking to consolidate and begin preparation for post GFC production. Straits Resources Limited were no different and despite having to deal with considerable difficulties themselves they began preparing the Tritton group of mining operations to process a minimum of 1.4 million tonnes or ore annually with the intention of producing 25,000 tonnes of copper metal a year. This meant the North East mine was to recommence production by mid 2010 of 300,000 tonnes a year.

The Tritton operation uses a traditional crushing and flotation technology at its processing plant. A method that produces a clean concentrate that is highly valued and sought after by smelters throughout the Pacific and Asian Regions. Early processing of ore from these operation was carried out by means of the SX/EW process. This being a hydrometallurgical process that takes place at ambient temperatures with the copper in either an organic or aqueous environment using sulphuric acid to reduce the copper in the ore to metal.

North East-Larsons Operations First Closed in 1999
Mining began on the Tritton lease as early as 1992 at the Murrawombie open pit mine, the first mine to be worked as part of the group of Girilambone open cut mines, which eventually included the North East- Larsons open pit operations. Open pit mining at Girilambone ceased in 1999 although the processing plant worked on for a further two years.

The North East Copper Deposit is Currently Open at Depth
Mining at the Tritton ore body itself began in 2004 with the decline being developed. Stope production began in March 2005. A pastefill plant to service the mine became operational in 2011, this increased recovery of copper ore from a previous 55 percent to a staggering 94 percent. At the present time the North East copper deposit remains open at depth.
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