Gold production for the first quarter of 2015 increased by 4% to 94,977 ounces, compared to 91,317 ounces in the prior-year period. The production increase was driven by a strong first quarter at Cerro San Pedro, offset with a production decrease at New Afton. The balance of the two operations remained consistent with the first quarter of 2014. At Cerro San Pedro, production increased by 50% to 25,950 ounces, compared to the prior-year period. This increase in production was driven by a 150% increase in ore tonnes mined and placed on the leach pad, coupled with a 30% increase in gold grade. At New Afton, the decrease in production was primarily the result of higher daily throughput at the mine, resulting in an increase in the grind size of the ore, leading to lower recoveries.
Gold sales were 92,398 ounces for the first quarter of 2015 compared to 94,052 ounces in the prior-year period. Despite an increase in production compared to the prior-year period gold sales were impacted by the timing of sales in the period.
Copper production for the first quarter of 2015 was 23.0 million pounds, compared to 25.9 million pounds in the prior-year period. The primary decrease in copper production was a due to New Afton. At New Afton, daily throughput at the mill has increased, resulting in a larger grind size which reduces recoveries. Subsequent to the end of the first quarter of 2015 the Company has commissioned the new vertimill, as part of the mill expansion project, which will increase the grinding capacity of the mill and will optimize grind size yielding improved recoveries. At Peak Mines, the 0.5 million pound decrease in copper production relative to the prior-year period was due to the decrease in ore tonnes processed.
Copper sales were 22.1 million pounds for the first quarter of 2015 compared to 25.1 million pounds in the prior-year period. This decrease was driven by decreased copper production from both New Afton and Peak Mines for the first quarter of 2015.
Silver production for the first quarter of 2015 was 0.4 million ounces, consistent with the 0.4 million ounces in the prior-year period. At Cerro San Pedro, the increase in ore tonnes mined and placed was offset by a decrease in silver grade. The silver contribution from New Afton and Peak Mines remained consistent with the first quarter of 2014.
Total cash costs per gold ounce sold, net of by-product sales, were $486 per ounce for the first quarter of 2015, compared to $254 per ounce in the prior-year period. The increase in total cash costs relative to the prior-year period was primarily a result of a $21 million, or $209 per ounce, decrease in copper and silver by-product revenues, driven by a combination of lower by-product sales volumes and realized prices. The impact of the lower by-product revenues coupled with lower gold sales volumes was only partially offset by the depreciation of the Canadian and Australian dollars and Mexican peso relative to the U.S. dollar.
All-in sustaining costs per gold ounce sold were $1,014 per ounce for the first quarter of 2015, compared to $674 per ounce in the prior-year period. This increase was primarily due to the planned waste stripping costs incurred at Mesquite which will provide improved access to ore in the second half of 2015 and 2016 and the higher cash cost component partially offset by a decrease in corporate administration and exploration.
Subsequent to the quarter the mill expansion project at New Afton was being commissioned, ahead of schedule and below budget. The Vertimill was successfully commissioned in mid-April approximately one month ahead of schedule with additional flotation cells currently being commissioned. The project capital cost of approximately $35 million is $10 million, or 22%, below budget, attributable to combination of project execution and depreciation of the Canadian dollar relative to the U.S. dollar since the project budget was established in 2014.
