New Century said ramp-up activities were now focused on optimising concentrate product quality through the zinc cleaner circuit (followed by zinc and silver recoveries), as well as plant throughput.
Century has an estimated production capacity of 264,000t per annum of zinc and three million ounces per annum of silver over an initial mine life of 6.3 years.
The tailings reprocessing venture aims to produce zinc at so-called C3 cash costs of US50c per pound, generating average life-of-mine earnings (on an EBITDA basis) of A$449 million per annum using a long term zinc price of US$1.25/lb.
New Century shares were up 1.3% to A$1.18 per share in early trade, capitalising the company $595 million.
The stock has spent much of the past 12 months trading within a range of about $1.20-1.40 per share.
Cash at the start of the current quarter stood at about $65 million.