Port gregory

From very humble beginnings 30 years ago this year (2013), the Port Gregory garnet mine in Western Australia has grown to become the world's leading producer of garnet abrasives and it still has resources in excess of eight million tonnes to fall back on.

Port Gregory Garnet Mine Owned and Operated by GMA Garnet Pty Ltd
The Port Gregory garnet mine, that is owned and operated by GMA Garnet Pty Ltd, has already produced over a million tonnes of non-toxic, highly refined industrial grade garnet from its processing and mining operations located in the Mid West Coast Region near Geraldton.

Port Gregory Garnet Processed On-site and at Geraldton
Garnet is mined at Port Gregory from highly mineralised sand dunes and taken by dump trucks to ore stockpiles before some of it is fed into hoppers at the GMA wet processing plant. Garnet bearing ore is also taken to Geraldton to be processed at a dry processing facility that operates 24 hours a day every day of the year to produce over 400,000 tonnes of heavy mineral concentrate a year.

The garnet concentrate is fed through rotary dryers that are natural gas fired and exposed to rare earth magnetic separators that remove any existing impurities.. All non-magnetic minerals are spun off in an outer cut. The remaining garnet mineral that has been separated during this process forms a middle stream which the more magnetic minerals fall below. The resulting refined and pure garnet concentrate is then passed through a series of vibrating screens that grade the product into different sizes.

The wet concentrator exposes the garnet bearing ore to spiral classifiers that make use of water and gravity induced centrifugal force. This separates the garnet from the lighter impurities and any shell sand. Hydrosisers make use of upward flowing water with the resulting slurry being density controlled so it is able to lift out any fine minerals. The garnet concentrate that has been produced is then transported along a vacuum filter belt that takes it through various stages of washing with clean water to make certain the final product has a low chlorine level.

Port Gregory Garnet Packaged in 25 kilogram and two Tonne Bulk Bags
After finishing the garnet off at the dry processing plant the product has to be packaged. This is undertaken with automatic double spouted bagging machines that are capable of filling 25 kilogram packs by means of robotic palletising equipment. Loose garnet is packaged in bulk bags that can contain two tonnes of garnet in each bag. The packed garnet is stored in warehouses located at the plant at Geraldton, as well as in Perth at the group's logistic centre. The garnet is exported out of Australia in shipping containers in the packaged form.

Bulk garnet is also stockpiled in storage facilities at the Geraldton port from where it is shipped out of the country in loose bulk loading conditions to be taken to regional bulk warehouses and packaging plants around the world.

Garnet from the Port Gregory Mine has been used as a blast medium on structures around the world including pipelines and shipbuilding as well as on the Sydney Harbour Bridge.
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