PERTH (miningweekly.com) – Diversified miner Rio Tinto has reported significant improvements in its iron-ore production and shipments during the third quarter, with CEO Sam Walsh saying the Pilbara operations had benefited from expanded infrastructure.

Rio produced 86.1-million tonnes of iron-ore in the three months ended September 30 – representing increases of 8% quarter-on-quarter and 12% year-on-year.

Global iron-ore shipments reached 91.3-million tonnes, up 12% on the previous quarter and 17% on the third quarter of 2014.

The higher iron-ore production was achieved through productivity gains and the ramp-up of the Namuldi operations, with the Pilbara operations producing 227.6-million tonnes in the first nine months of 2015, of which Rio’s share was 185.1-million tonnes.

Copper production for the third quarter was down 14% on the previous quarter, and 24% on the previous corresponding quarter, to 115 000 t, as Rio’s focus at the Kennecott Utah copper project remained on deweighting and dewatering the east wall of the Bingham Canyon.

The Escondida operation also reported lower production, owing to lower grades and the planned shutdown of the Laguna Seca concentrator for maintenance activities.

In conjunction with the lower grades, production at Escondida was also impacted by water availability in the quarter under review.

Meanwhile, the Oyu Tolgoi project continued to ramp up, with copper production up 53% compared with the previous corresponding period, to 18 800 t, on the back of higher grades and improved throughput.

Rio on Friday reported that hard coking coal production was down 12% quarter-on-quarter, while semisoft and thermal coal production was up 9%, to 1.85-million tonnes and 5.54-million tonnes respectively.

Bauxite production was also up by 6% quarter-on-quarter, to 11.2-million tonnes, while aluminium production was up 1% to 830 000 t.

Diamond production from the Argyle mine was up 4% on the previous quarter to 3.5-million carats, as Rio’s focus remained on the ramp-up of production from the underground mine.

At Diavik, third-quarter carat recovery decreased by 41% quarter-on-quarter, to 761 000 ct, owing to lower processing volumes and lower recovered grades.

“We continue to deliver efficient production, rigorous cost control and sound allocation of capital,” Walsh said on Friday.

“Our cash generated from operations will enable us to deliver strong returns to shareholders through the cycle and our balance sheet will be further strengthened by recent divestment activity.”