TVI Pacific has commenced nickel production at its plant at Intertek Minerals Philippines in Manila.
The company said that a pregnant leach solution was passed through a counter-current ion-exchange (IX) pilot plant and recovered about 99.3% of the nickel.
A nickel hydroxide product (NHP) filter cake was produced from the plant, with a 52% to 54% nickel grade.
TVI said positive results were received from the pilot plant at the Beijing General Research Institute of Mining and Metallurgy (BGRIMM), which marks a key step for the Agata North project, located in the mining district of Agusan in northern Mindanao.
BGRIMM has also produced a mixed hydroxide product (MHP) with an average of 36% nickel, which after a two-stage precipitation process could be improved to a grade of more than 40% nickel.
TVI Pacific vice-president of operations Jake Foronda said: "The pilot tests confirm the viability of a two-stage atmospheric leach process in producing NHP containing about 50% nickel or a MHP containing some iron."
The final stage of plant operation will involve the treatment of the barren solution from the IX plant, to produce an effluence that is acceptable for disposal, as well as ecological tests for residues.
TVI and Mindoro Resources have signed four joint venture agreements relating to the Agata and Pan de Azucar mining projects located in the Philippines, on the islands of Mindanao and Panay, respectively.
TVI's affiliate, TVI Resource Development, has to date produced copper and zinc concentrates from its Canatuan mine and is advancing its Balabag gold-silver project and its Agata nickel direct shipping ore operation.