King of the Hills Gold Mine (Tarmoola; KoTH), Leonora, Leonora Shire, Western Australia, Australiai

Regional Level Types
King of the Hills Gold Mine (Tarmoola; KoTH)	Mine
Leonora	Town
Leonora Shire	Shire
Western Australia	State
Australia	Country

The King of the Hills Gold Mine (often shortened to KoTH), is 30 kilometres north of Leonora, and about 2 kilometres west of the Goldfields Highway. In the early 19th Century, and again in recent times it was known as King of the Hills, but with early open pit development from 1985, it was called Tarmoola.

The site contains a giant open pit, where one side of the wall has either collapsed, or been partly filled with waste. There is a far smaller water filled open pit immediately south called Galahad. A shallow pit called Leighter's was just south of the entrance road, mined in the early 2000's, now filled in and rehabilitated.

Once the Tarmoola open pit mining ceased, underground operations commenced from the base of the Tarmoola pit. At the time of writing there was still much buildings, drums, equipment at the site, as the mine was active from 1985 to 2004 as an open pit, then by St Barbara as an underground mine from 2011 to 2014. During the open pit period the mine produced 1.6 million ounces from high volume low grade ore. During the underground period, the mine was producing 60 000 ounces a year. Saracen purchased the mine in 2015, with intentions to re-open it, so the above description could change within a very short time.

Like many of the deposits in the Leonora area, it started as a prospector show in 1897, and was active till about 1920. The lease contained several shafts. Early owners included Humphries (surname), Sid Fowler, J.M.D. Williams.

The King of the Hills Gold Mining Company was formed in 1912, however had little success and abandoned the property. As a prospector show, it appears to have had variable crushing outcomes from sensational, to barely covering costs.

After 1912, Bob Hasted and Herb Cottingham working the mine for several years, until an influx of water forced them to abandon it. In 1917, it was being worked by Bradburn and party. Henderson and Legg in 1920. Until modern mining took place little was then found, except a crushing in 1933 by Coratti (surname), and 1947 by C.H. Dunn.

Gold is found in sheeted and faulted quartz vein sets, within a granodiorite stock, and enveloping carbonated ultramafic unit, where it intersects the major regional northern section of the Sons of Gwalia Shear Zone.

The mafic shear zone to the east as the McGrath's or Ockerburry Fault defines the boundary with the Gindalbie Domain. Gold is hosted in a large trondhjemite granite pluton, and overlying strongly foliated ultramafic and mafic sequence. The north-east trending pluton is bounded by two major north-east trending structures called Ursus and the Tarmoola Faults, extending off the Poker Fault to the south.

Mineralisation has developed in a sinistral reverse brittle/ductile shear zone within the main thrust shear zone, forming the primary conduit for mineralised fluids. Pre-existing quartz veining and a network of brittle fracture faults in the granite created a secondary conduit for the fluids. Gold developed during a strong south-east to north-west compression.

Quartz lodes and shear veins often form anastomosing structures from 20 cms to 2 metres wide. The lode contain complex overprinting zones of grey laminated quartz, and barren white quartz, reflecting a fault valve mechanism. Breccia zones with angular wall rock fragments in quartz is common at the lode margins.

Gold occurs as free particles, and also associated with galena, chalcopyrite, pyrite and sometime sericite, with fuchsite also present in the north-east portion of the granite as a East and West Flank zone. These zones converge onto the east flank of the granite.

The Tarmoola, Ursus and Poker Faults are early shears during the extension and uplift of the Raeside Batholith, and were re-activated as sinistral strike slip shears during the subsequent compression period. This resulted in the granite body being rotated anticlockwise, and the development of a damage zone, or hinge along the eastern contact of the pluton, where the gold is found.

At the mine, abundant north-east and north-west trending oblique dextral faults overprint the other structures and lodes. There are also steeply plunging planar faults overprinting the other structures formed late in the brittle regime.

Other Regions, Features and Areas containing this locality

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