Hidden valley

The Hidden Valley gold and silver mine, located in the Morobe Province of Papua New Guinea, is an open pit operation that has its gold and silver dore refined at the Perth Mint in Western Australia. The mine is situated 90 kilometres south west of the Lae port and 300 kilometres north west of Port Moresby.

Hidden Valley Mine Owned and Operated by Morobe Mining Joint
Ventures
The Hidden Valley open pit gold and silver mine is owned as a joint venture operation between Harmony Gold Mining Company of South Africa (50 percent) and Newcrest Mining Limited of Australia (50 percent). The joint venture, that was formed in 2008, is known as the Morobe Mining Joint Venture (MMJV). It is also the mine's operating company.

MMJV was originally created for the purposes of exploration, development and the operation of mines in the Wau Bulolo district of the Morobe Provence in Papua New Guinea and the Hidden Valley mine was the company's first project to reach production stage.

Hidden Valley Mine Construction Began in 2007
The Hidden Valley gold and silver mine comprises three main lodes, these being the Hamata, Kaveroi and Hidden Valley lodes. Construction of the mine began in 2007 with production commencing in 2010. It is still in the process of ramping up production to its target level of 250,000 ounces of gold a year along with between 2.5 and three million ounces of silver. At the end of the 2012/13 financial year the Hidden Valley mine was producing 170,008 ounces of gold annually along with 1,712,656 ounces of silver.

Hidden Valley Mine Employs 2,600 Personnel
The Hidden Valley gold and silver mine is mainly a fly-in-fly-out open cut mining operation that employs around 1,000 people directly and a further 1,600 as contractors, most of whom live at the on-site accommodation village. The mine is located at an altitude of approximately 2,000 metres above sea level and experiences high rainfall.

Hamata pit ore is taken by truck to the Hamata crusher plant before it is taken by conventional conveyor to a primary stockpile. Ore from the Hidden Valley crusher plant is transported by means of a 4.5 kilometre long overland pipe conveyor directly to the Hamata processing plant. The crusher plants use two jaw crushers in series to make the ore transportable and able to be fed into the semi-autogenous (SAG) mill.
The Hidden Valley processing plant consists of a Merill Crowe circuit to separate silver and conventional gravity and CIL circuits to separate the gold. The mill is able to process 4.2 million tonnes of ore a year from the Hidden Valley and Hamata open pits. When commissioning ends the plant will be able to handle 4.7 million tonnes of ore a year.

Hidden Valley Mine Agreement Protects Local Workers Rights
The Hidden Valley open pit gold and silver mine operates under a Memorandum of Agreement between all levels of government, the local people and the Morobe Mining Joint Venture. The agreement protects the employment interests of landowner and local residents before those of any other PNG provinces, or offshore workers, whenever experience and qualifications are otherwise equal.
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