Nifty is a historical copper mining site in the north-eastern Pilbara region of Western Australia. The mine complex has been owned and operated by Metals X since 2016.
An underground copper sulphide mine along with a 2.8 million tonne per annum (Mtpa) copper concentrator has been placed on care and maintenance since November 2019, while a scoping study for a major expansion to a pre-existing oxide open-pit mine at the site was completed in June 2020.
The study calls for an average annual production of up to 26,000 tonnes of copper in concentrate from an open-pit and heap leach operation by treating up to 2.3 million tonnes per annum (Mtpa) of sulphide ore over an estimated mine life of ten years.
The total capital cost for the open-pit sulphide operation is estimated to be £105m ($131m) that includes approximately £53m ($67m) of pre-production capital and approximately £52m ($67m) of the life of the mine (LoM) operating cost.
The ore production from the open-pit mine is expected to be started after the completion of a feasibility study (FS) in 2021.
History of the Nifty copper mine
The oxide copper resources at Nifty were discovered by WMC Resources in 1981 while the underground sulphide resources were discovered in 1983.
The open-pit, heap leach operations at the site were started in 1993, and the mine was acquired by Straits Resources in 1998 which operated the mine for five years and sold the property to India-based Aditya Birla Minerals in 2003.
The underground mine development via a decline from the open-pit as well as the construction of a sulphide concentrator was started in 2004, while the first concentrate was produced in March 2006.
The open-pit operations were stopped in June 2006, while the heap-leach operations were discontinued in January 2009.
Metals X became the owner and operator of the mine by acquiring Aditya Birla Minerals in 2016.
Location, geology and mineralisation
The Nifty copper mine is situated on the western edge of the Great Sandy Desert in the north-eastern part of the Pilbara region in Western Australia. The project site is approximately 350km to the southeast of Port Hedland.
The Nifty copper deposit is hosted by the Yeneena Supergroup within the Neoproterozoic Broadhurst Formation which is spread over 24,000km2 and forms part of the Paterson Orogen.
The host rocks in the deposit are classified into four categories namely, the Footwall Beds, Pyritic Marker, Nifty Carbonate Member and the Hangingwall Beds.
The copper occurrence within the deposit is characterised by supergene oxide, sulphide and transitional mineralisation overlying the stratabound hypogene sulphide mineralisation.
The main sulphide minerals in the deposit are chalcopyrite and pyrite, with minor amounts of sphalerite and galena.
Copper resources at Nifty
The Nifty mine is estimated to hold a total of 53.13Mt of measured, indicated, and inferred ore resources grading 1.2% Cu and containing a total of 637,700t of copper.
Mining and ore processing for the Nifty open-pit mine
The conventional open-pit mining involving drill, blast, load and haul methods will be implemented at the Nifty copper mine.
The extracted ore will be trucked to the existing 2.8Mtpa copper concentrator and the 25,000 tonnes per annum (tpa) heap leach solvent extraction and electrowinning (SX/EW) facility at the site.
The existing sulphide copper concentrator facility houses a primary jaw crusher, a semi-autogenous grinding (SAG) and a ball mill, apart from the flotation and filtering circuits, concentrator thicker, tails thickener and a paste fill plant.
Apart from the existing concentrator and heap leach SX/EW facilities, the proposed Nifty open-pit operation will also utilise the existing 21MW gas-fired power station along with the existing water supply systems, waste dumps and tailings storage facility, accommodation village and all-weather airstrip.
Copper off-take from Nifty
The copper concentrate produced at the Nifty copper mine will be sold to Hindalco Industries of India, under an existing off-take agreement with Metals X.
Mining Plus undertook the pit-optimisation study as part of the scoping study for the Nifty open-pit copper mine.