Juno Mine ('Peko'; Explorer 8), Tennant Creek, Barkly Region, Northern Territory, Australiai

Regional Level Types
Juno Mine ('Peko'; Explorer 8)	Mine
Tennant Creek	Creek
Barkly Region	Region
Northern Territory	Territory
Australia	Country

A major gold-copper-bismuth mine closed during November, 1981.
Owned by Gecko. Hosted by ironstones.

The mine hosts three type locality species, being junoite, pekoite, and proudite. Location wise, the first two are uncommon, and the proudite is rare. The species belong to lead and bismuth seleniferous sulphosalts, rarely found in sulphide deposits, and in the past often poorly defined as individual species.

Specimens will often be labelled Juno Mine (Peko) however, it should be noted that Juno and Peko are separate mines, about 2 kilometres apart. The Pekoite species type locality is the Juno mine, it is assumed the name comes from the company (Peko-Wallsend) that mined both deposits. In turn, 'Peko' for the original deposit, is named after a dog.

The original sources describing the type locality material, obtained samples for the mine from outside collections, so shed little light of where the species fit into the overall geology of the mine.

When operational, Juno was the highest grade gold mine in Australia. The Juno lode is vertically zoned with magnetite (80%) and chlorite (20%) forming its core, enclosed by talc-magnetite and minor pyrite, then a thin dolomite zone, and finally chloritised country rock. Gold is concentrated in the core, surrounded by an umbrella shaped bismuth sulphosalt zone, formed by hydrothermal processes at low temperatures. Bismuthinite is concentrated in the basal part of the sulphosalt zone, with chalcopyrite more prevalent in the upper parts. The whole deposit is part of an anticline.

Proudite is named after John S. Proud (1907-1997), a director of the Peko-Wallsend Mining Company. It was initially mis-identified as wittite, due to the rarity of the species, and poorly defined chemical studies on it. Shortly after it was proved to be a new species, and named proudite. It contains 6.5-15.3% Se. The specimen studied came from the University of New England collection. Pekoite is composed of two slabs of bismuthinite and one of krupkaite as ribbons alternating along the B axis as a three fold superstructure. Junoite is up to 11.4% Se.

The deposit before the mine was created was called Explorer 8. Three drill holes had produced negative results in 1954, from what was otherwise a very promising magnetic anomaly. John Elliston purchased the lease for 50 pounds, and continued drilling uncovering the rich but small deposit in 1965. Production commenced in 1968, achieving 838 941 ounces of gold from 346 235 tonnes of ore at 73 g/t, with minor bismuth, silver, and selenium. Peko-Wallsend (Geopeko) operated the mine, along with several rich mines in the area at the time. Ted Davies was area manager, known as Terrible Ted, for terrorising younger less experienced staff.

The underground mine contained a head frame, small processing plant, a few demountable buildings and nearby caravan park for workers. The mine closed in 1981. Several exploration companies have conducted near surface drilling to examine the potential of an open cut mine. The mine site is about 2 kilometres south-west of the Peko mine, or 8 kilometres south-east of Tennant Creek. Little appears to remain at the site apart from some cleared areas and building foundations. The former workman's camp on the road into the mine, is now a public camp site.

Other Regions, Features and Areas containing this locality

References