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Applicable Equipment


Award-winning, portable processing plant for high recoveries by gravity separation.


Flexible plant components for versatile, cost-effective flowsheets.


Also applicable to other Gekko products such as the Mag Screen.

Applicable Minerals


Free gold is unbound to other materials and is easy to liberate.


Gold associated with sulphides requires a modified flowsheet.


Free silver and silver complexes behave unpredictably and contain impurities.

Applicable Minerals


A combination of different metals in a single compound.


Such as tin/tantalum, diamond, garnet and other gemstone-containing material.

Feed Preparation

‘Feed’ is any material that is fed into a machine at any stage during the mineral recovery process. However, feed preparation for gravity circuits is a primary focus because Gekko Systems develop energy-efficient gravity concentration flowsheets.

Problems can arise when slurries with high magnetic material or viscosity are fed into gravity separation devices.

Therefore, correct testwork characterisation of the ore, followed by ore-specific feed preparation measures are needed. This will maximise the use of the gravity device for improved recoveries and better operating costs.

Gekko develop feed preparation processes that bolster recoveries.


Maximise the use of any gravity concentration device for greater gold mass recoveries.

Smart magnetic screening of the feed produces a cleaner, higher-grade material for gravity concentration.

Upgrading feed preparation with a better flowsheet design and retrofitted installation is straightforward.

Hands free, low maintenance, long-lasting feed preparation circuits are available for robust operation.

Correct preparation of feed for gravity concentration circuits will provide enormous cost savings and enhance mineral yields.

Consuming less water in the feed preparation has a positive environmental impact.

How It Works

To reduce the material mass for downstream processing, or to maximise gravity separation as a first step, the correct feed preparation is important.

Prior to presenting feed to any gravity concentrator it's important to know what constitutes the ore and how best to prepare it, to achieve the highest returns from downstream processes.

Oversize particles can choke pumps, block gravity units, rapidly wear out equipment, and reduce separation efficiency and recovery of fine valuable material. In addition, dilution of material with water must be balanced, i.e. not enough can lead to suboptimal classification of fractions while too much water can disrupt the overall circuit efficiency.

When a higher grade feed material is supplied to a gravity separation device, for pre-concentration of high value material or gangue rejection, greater recoveries are achieved. Magnetic screening before gravity separation can increase feed grade considerably and enhance the subsequent output from any gravity concentrator.

The Gekko Difference

Gekko’s specialty is designing complete gravity flowsheet solutions, therefore, Gekko also develop feed preparation processes that bolster gravity concentration recoveries. Combining several Gekko technologies in the same circuit can yield great results when two separate size fractions are targeted.

Removing non-valuable material, using Gekko’s MagScreen, improves grinding capacity and reduces the burden on the gravity concentrator. This long-lasting, low maintenance screen can be easily retrofitted to maximise recoveries. Then Gekko’s Inline Pressure Jig (IPJ) can function optimally to recover gold-bearing particles when contaminating magnetics are not present.

Gravity separation devices, such as the IPJ, are relatively simple. However, the surrounding engineering, including incoming feed preparation, can be complex. Higher recoveries are possible when feed input and feed properties are optimised for the downstream gravity recovery step.

Preliminary testwork is critical to understand an existing circuit’s performance, a unique ore deposit and identify the optimum particle size fraction(s) for the best return. It’s essential that sampling tests be performed by Gekko’s technical services team, before or during the design phase of a feed preparation process, to produce a safe, practical, economical operating circuit. Gekko will provide expert recommendations for developing the most efficient, environmentally responsible feed preparation for gravity circuits.

Feed preparation recommendations can also be sought from Gekko Systems for other grinding circuits such as silver, coal, polymetallics and other minerals. Gekko understand many feed preparation scenarios and offer technical assistance in this area. Contact the Gekko technical services team today.

Powell Ball Scats Removal

Technical Papers (3 of 52)

More Technical Papers
technical paper
Technical Paper 017 - Feed Preparation For Gravity Separation In Grinding Circuits

Gravity, Perth, Australia. Sandy Gray. | 01 March 2004

technical paper
Technical Paper 011 - A New Age Gold Plant Flowsheet

AusIMM - Metallurgical Plant Design and Operating Strategies Conference. Rob Longley, Nick Katsikaros and Chris Hillman. | 01 April 2002

technical paper
Technical Paper 010 - Powell Ball Scats Removal

Mining & Mineral Process Engineering, Vancouver, Canada. Malcolm Powell and Ian Smit. | 01 June 2001

Positive Recovery Results from Python at Kloof

Articles (3 of 88)

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The Python 500 modular processing plant was originally developed to process ore in an underground environment. | 01 September 2012

Positive Recovery Results from Python at Kloof

Gekko Systems was contracted by Gold Fields in June 2010 to design, build, install and commission a Python 500 modular plant for its Kloof GROWTH project in South Africa. | 01 July 2011

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