TORONTO (miningweekly.com) – Canadian diversified resource company Sherritt International on Thursday reported that full-year 2014 finished nickel output from its Ambatovy nickel and cobalt mine, in Madagascar, rose 47% over the previous year, as well as by the same percentage in the December quarter, compared with the fourth quarter of 2013.

For December, Sherritt-attributable finished nickel output totalled 1 302 t, and finished cobalt output totalled 76 t. On a 100% basis, Ambatovy produced 3 254 t of nickel and 189 t of cobalt.

Ambatovy's 2014 production was 37 053 t, which was in line with the 2014 guidance range.

For the month of December, ore throughput in the pressure acid leach (PAL) circuit was a record 417 412 t, or about 83% of nameplate capacity, and finished nickel output represented about 64% of nameplate capacity.

The Ambatovy Joint Venture (JV) partners said they had moved forward maintenance on autoclaves and other components to create a window in mid-2015, when the plant is operating at an optimum level, to give them the best chance of reaching commercial production, which was defined as 90% of design capacity for 90 days.

Ambatovy is expected to produce 54 000 t/y of finished nickel.

Sherritt noted that one autoclave in the PAL circuit returned to service in mid-December after planned maintenance was executed, while planned maintenance activities for the refinery continued in early December, which partially impacted finished nickel volumes for the month.

Planned maintenance was complete on four of the five PAL autoclaves and planned maintenance would start on the fifth autoclave in February.

Sherritt remained focused on the ramp up of production at Ambatovy and was currently working towards the key milestone of reaching a production rate equivalent to 54 000 t/y of nickel, about 90% of nameplate capacity. The production rate was measured over 90 days in a 100 day continuous period and the target to achieve this milestone was mid-2015.

The Ambatovy JV is a vertically integrated nickel and cobalt mining, processing, refining and marketing JV between subsidiaries of Sherritt (40%), Sumitomo (27.5%), Korea Resources (27.5%) and SNC-Lavalin (5%). Sherritt is the operator of the facilities.