Granny smith

The Granny Smith underground gold mine in Western Australia is a part of the Gold Fields operation that is made up of the Darlot- Centenary and Lawlers gold mines as well at the Granny Smith Mine.

Granny Smith Mine has a First Class Processing Plant

The Granny Smith Mine has a first class processing plant that is also used by other mines in the district. It consists of a two stage ore crushing circuit that utilises closed circuit screening along with a single stage oxide ore crusher, a semi-autogenous grinding mill in closed circuit with a cone crusher, agitation leaching and a CIP (carbon in pulp) circuit. There is also a fine grind gravity treatment plant and a carbon reactivation gold recovery facility as well as a tailing thickener. Gold reserves at the Granny Smith mine at the end of 2012 stood at almost two million ounces.

The Granny Smith processing plant is capable of processing greater volumes that that produced by Gold Fields three mines that make up the Yilgarn South Operation. For this reason it also processes ore that Gold Fields purchase from Focus Minerals nearby Laverton operations. The plant underwent improvement in 2012 that consisted of screen size changes, optimisation of crushers and ball loading in the mills. These changes delivered greater mill throughput. Where it was capable of handling 7,500 tonnes a day before the changes were made it is now capable of handling 9,000 tonnes per day.

The processing plant handled 920,000 tonnes of ore that was mined underground in 2010 and this has now been ramped up to over 1.4 million tonnes. This resulted in gold recovery rising from 139,000 ounces in 2010 to 200,000 ounces in 2012.

To provide the increased throughput to the mill the Granny Smith Mine has also benefited from increased haulage truck capacity and the purchase of a new Jumbo that can drill more holes into the rock face each day for blasting. The more faces drilled, or the longer the holes drilled, equates to the more tonnes of ore that can be blasted free to be put through the processing plant.

Mine Workers Invent a new Low Profile Tyre Handler

The Granny Smith Mine is operated using mining industry best practice procedures at all times and it doesn't avoid the adoption of innovation when confronted with a better way of doing things. No better example can be held up than that of the new low profile tyre handler. This innovation was developed by the Granny Smith maintenance team in conjunction with Perth company Austin Engineering and is now used in all Gold Fields Western Australian mines as well as in the USA.

The low profile tyre handler came about as it was always difficult to change tyres on equipment underground because of the limited space to work in between the wheel arch and the tyre itself. Mine workers had always been subjected to danger when balancing heavy industrial tyres on fork lift tines. The mine workers therefore saw a need for a mechanised tyre handler and set about giving it some thought. It had to be a machine that could support, grip, rotate and tilt tyres of many different sizes and on equipment with little wheel arch clearance. A prototype was designed and Austin Engineering were asked to build it. It was an immediate success.

Granny Smith - an Appropriate Name Under the CircumstancesrnThe Granny Smith Mine derived its name after the deposit was discovered by a man named Ray Smith in 1979. At the time of making the discovery his wife Laurende had just become a grandmother. The honour was made and the name has stuck ever since.