Owendale scandium project, also known as the Platina scandium project, is located in central New South Wales, Australia. It is one of the world’s highest grade scandium deposits and is expected to become the first scandium producer in the country.
Platina Resources, a precious and specialty metals exploration and development company based in Australia, is the owner and developer of the property.
The definitive feasibility study (DFS) for the project was completed in December 2018, which proposes a two-stage development of the mine with an estimated capital expenditure of $59.2m (£46.5m).
Stage one will produce 20 tonnes per annum (tpa) of scandium oxide during the initial five years of operation, while stage two will double the annual production capacity to 40t with the processing plant upgrade.
The estimated mine life is 30 years and the project has also the potential to produce cobalt, nickel, and platinum in future.
Owendale mine location and geology
The Owendale project comprises the development of Red Heart scandium deposit, which is located 53km north-east of Condobolin and 11km south-west of Tullamore.
The processing plant will be constructed near Condobolin, approximately 70km south-west of the mine site.
The scandium and platinum mineralisation is hosted in both ultramafic and intermediate intrusive rocks that stretch up to 50m-deep below surface. The scandium hosted in laterite is developed in Alaskan type intrusive complexes.
Scandium occurs in the clinopyroxenites, while platinum is found in the form of isoferroplatinum.
Owendale scandium project reserves
The proven and probable ores reserves at Owendale are estimated to be 4.02 million tonnes (Mt) at a cut-off grade of 450 parts per million (ppm) of scandium.
The mine is estimated to contain 3,512t of scandium, 3,599t of cobalt, and 4,821t of nickel in proven and probable reserves.
Mining and ore processing at Owendale
The Owendale scandium project is planned to be mined using open-cut mining techniques deploying hydraulic excavators and Moxy mine trucks.
Mining is expected to be commenced from small open-pits with no drilling or blasting planned. The ore will be mined and stockpiled for blending, and the blended material will be transported via road to the off-site processing facility.
Platina Resources successfully completed the pilot plant for testing the ore in June 2018. The ore is recovered from the mined stockpiles, crushed to 20mm, and ground in a closed circuit ball mill to a P80 size of 75µm, followed by thickening.
The ore goes through high-pressure acid leaching (HPAL) process comprising two-stage preheat, autoclave, and two-stage pressure letdown circuit. Thickening and filtration are carried out to produce pregnant leach liquor (PLS).
Solvent extraction followed by precipitation and filtration is carried out to recover scandium from the PLS. The filtered scandium solids undergo purification and calcination followed by drumming to produce the final scandium oxide product.
Partial neutralisation, thickening, and filtration are performed to produce partially neutralised liquor. Sulphide precipitation of nickel and cobalt followed by thickening and filtering is carried out to produce a mixed sulphide precipitate and barren solution, which is neutralised to produce neutralised slurry.
The slurry is thickened and filtered to produce tailings, which are transported back to the mine.
Owendale scandium mine infrastructure
The mine site is accessed through two existing vehicle entry points, which will enable transportation of the produced ore from the site.
The property also includes buildings, ponds, concrete pads, and a house that will be used as the initial office and site accommodation. A drilling programme is also planned to be carried to determine the quality of the groundwater, which will be used in the mining operations.
A dedicated rail facility is also planned at Owendale, which will connect with main east-west rail line running from Perth and Sydney.
Ausenco Services, a consulting, engineering and project delivery firm based in Australia, was contracted to carry out the definite feasibility study in March 2018.
Element 21 was engaged for scandium solvent extraction and refining, while ATC Williams carried out residue storage and geotechnical studies during the DFS.
R.W. Corkery & Co was engaged for environmental and permitting works, while Measured Group provided the mine planning.