Forrestania Rubellite pegmatite, Mount Holland pegmatite field, Yilgarn shire, Western Australia, Australiai

Regional Level Types
Forrestania Rubellite pegmatite	Pegmatite
Mount Holland pegmatite field	Pegmatite Field
Yilgarn shire	Shire
Western Australia	State
Australia	Country

Gem-grade pink tourmaline has been extracted from this site, however the pegmatite is intensely weathered. It is located 124 kilometres south of Southern Cross, in a gold and nickel mining region called Forrestania. The mine is presently (2012) leased by Fred Rose, who sells specimens from the mine on eBay.

Kim Robinson accidentally discovered the pegmatite while searching for nickel sometime between 1971 and 1976. Rubellite chips came up with the drill cuttings. He mined the site for tantalum in the early 1980s, discovering the new species kimrobinsonite, which is an alteration mineral of stibiotantalite. During this time, about 200 kilograms of manganotantalite and microlite concentrates had been produced from approximately 3,000 tonnes of ore. He also produced 1,400 carats of gem rubellite, and some of this was the finest gem-grade tourmaline produced in Western Australia. Mining ceased by the late 1980s and around 2000, the lease was purchased from Kim Robinson by Fred Rose, who has since conducted mining here for specimens.

The pegmatite is within a north-trending greenstone belt, and both the greenstone and pegmatite are covered by a red-brown laterite layer. The pegmatite is 1–4 metres thick, dipping gently to the north, with a pit 75–150 metres long, 30–50 metres wide, and 18 metres deep, together with a small shaft near the north-western rim of the pit.

The pegmatite is severely weathered both physically and chemically, with much of the feldspars, albite and microcline, altered to clay. Further fracturing and brecciation of unweathered core sections have altered some of the minerals left. What zoning can be seen shows a hanging and footwall zone of medium grained albite-quartz with schorl, microcline-quartz intermediate zone, and quartz-cleavelandite-lepidolite core.

This central section has produced pink tourmaline, and rarely green tourmaline, clear quartz crystals and pink morganite. Fist-sized schorl crystals are said to be common at the west end of the pegmatite. Stibiotantalite and Kimrobinsonite are found in the underground workings. Kimrobinsonite is a white, chalky, friable mineral to 5 mm, associated with black cesstibtantite (the first time the species was discovered in Western Australia).

One truckload of Giles Pegmatite rock was dumped at Mt Holland during the 1980s by Kim Robinson with the intent of processing it, composed of curly albite with columbite and muscovite masses. This material is said to be still found around the dumps, and does not belong to Mt Holland. Lat -32.17984, Long 119.7898. Co-ord 763041 mE, 6436217 mN.

Other Regions, Features and Areas containing this locality

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