The Port Gregory Garnet Project is a 226 sq km Western Australian tenement package 100% owned by Heavy Minerals Limited. The project contains a JORC Compliant Mineral Resource estimate of 135 Mt @ 4.0% (THM) with 4.9 Mt of Contained Garnet.
The Company’s recently completed Scoping Study demonstrates the potential for a 16 year mine life project having a net present value (NPV) of $253 million and a capital cost of $110 million.
The Port Gregory Garnet Project is in the established mineralogical terrain of the Hutt River Garnet area within the Shire of Northampton in the mid-west coastal region of Western Australia.
It is situated approximately 45-60 km north of Geraldton, 45-65 km south of Kalbarri, and 40 km north-west from Northampton.
The Port Gregory Garnet Project borders GMA’s active Port Gregory garnet mine and the RDG Lucky Bay Mine (under construction).
The tenements are located over an area of heavy mineral deposits in Western Australia which are ultimately, but indirectly, derived from the weathering of crystalline igneous rocks in the Archean Yilgarn Block. Heavy mineral grains derived from the Yilgarn Block were initially deposited in thick sequences of Mesozoic sediments that filled the Perth Basin. The tenement area lies in the most northerly part of the Perth Basin, on the western side of the Northampton Block.
The Tamala Limestone, a belt of coastal limestone extends up to 8.0 km inland. It is composed of eolianite, which accumulated originally as coastal sand dunes in the late Pleistocene. This has developed over a basement of late Cretaceous age Winning Group sediments which can be seen outcropping near Yanganooka Well. A number of erosional scarps have been developed on the seaward side of the Tamala Limestone, one of which is equivalent to the strand-line mineralisation to the south. Fossil crescent dunes can also be distinguished on top of the large massive limestone area which may be of early Pleistocene age.
The sands contain significant localised enrichments of heavy minerals, notably garnet (almandine variety) and to a lesser extent ilmenite. The heavy minerals are thought to be derived from garnet-bearing Precambrian Granulites and migmatites of the Northampton Shield. The sands appear to have been deposited when the sea level was about 6m higher than today, possibly during the last interglacial peak.
Heavy Minerals will commence both in-fill and extension drilling at the Port Gregory Project in the third quarter of 2022.