TORONTO (miningweekly.com) – Canadian miner Iamgold on Wednesday said it had lifted the National Instrument 43-101-compliant indicated resource at its Côté gold project, in northern Ontario, by 114% from the previous resource estimate reported in October 2012.

The company said most of the mineral resources at the project had now been upgraded to the indicated category.

The new Côté gold resource estimate incorporated assay results from 85 additional drill holes, comprising 47 325 m since the October 4, 2012 estimate, and now entails 269-million tons grading 0.88 g/t for 7.61-million ounces and an inferred resource of 44-million tons averaging 0.74 g/t for 1.04-million ounces.

The estimate used a cutoff grade of 0.30 g/t of gold, similar to the cutoff used in the previous resource estimate.

The company said a positive attribute of the Côté gold deposit is its accessibility for openpit mining. The deposit locally outcrops at surface and, based on the drilling to date, the depth of the barren overburden averages 5.8 m.

Meanwhile, Iamgold also reported the fourth quarter of 2012 was its strongest, during which it produced 214 000 attributable ounces, which brought its 2012 attributable gold production to 830 000 oz, below the low end of its revised guidance of 840 000 oz to 910 000 oz. The company said the below-expectations-production was mainly owing to its underperforming joint venture (JV) operations.

The company in November cut its 2013 production target to this range from an earlier forecast of 1-million to 1.1-million ounces. At the time, it cited poor performance at its Sadiola mine, in Mali, and a slower ramp-up at the Westwood project, in Quebec.

“While performance at our Iamgold-operated mines has been solid, the underperformance at Sadiola has led us to reassess our strategy with respect to our joint venture operations,” Iamgold CEO Steve Letwin said.

The company expected the average total cash costs, including royalties, per ounce to be near the upper end of the $670/oz to $695/oz guidance range.

Iamgold said it expected to produce between 875 000 oz and 950 000 oz of attributable gold ounces in 2013, with total cash costs expected between $850/oz and $925/oz.

However, the company maintained its forecast to grow production by about 80% over the next five years to between 1.4-million to 1.6-million ounces by 2017.

The company, which operates in JV the Sadiola and Yatela mines, in Mali, said the recurrent conflict had not disrupted production at the company’s operations, but exploration activity had been reduced as a precaution.

The company’s stock listed on the Toronto bourse reacted negatively, shedding 9.64% of its value in morning trade to trade at C$9.75 apiece before noon.