The WA minerals and petroleum industry posted 2013 financial year revenue of $A101.8 billion, down 3.8% on FY12, though it was the third consecutive year sales have topped $100 billion.

Thanks to mining giants BHP Billiton and Rio Tinto – and to a lesser extent, Fortescue Metals Group – iron ore remained the state’s highest value commodity, notching up sales of $56.4 billion or 73% of total mineral sales.

The growth in exports from the major producers was enough to offset extreme volatility in iron ore prices, with the spot iron ore price briefly falling below $US90 per tonne in September last year.

WA producers exported 513 million tonnes of iron ore in FY13, up 13%, while the value of sales dropped 7.3%.

That is likely to continue in the current financial year with Rio, BHP, FMG and Atlas Iron all planning production growth through expansions and/or productivity improvements, while iron ore prices have sat at around $130/t for some time, bettering analysts’ expectations.

The petroleum sector, including crude oil, condensate, LNG, natural gas and LPG, was the second largest contributor at $A24.5 billion, up 2.9%, with LNG sales reaching a record.

Unsurprisingly, gold was the second-largest mineral contributor, accounting for $9 billion or 12% of sales, though the drop in the gold price in the first half of this year saw sales fall by 4.6%.

It was followed by alumina and nickel, though the values of both were hit by lower metal prices.

Nickel sales increased by 9.5% to a record 228,000 tonnes but the total value decreased by 2.3% to $3.6 billion, while the total value of alumina decreased by 1.3% to $3.9 billion despite an 8.9% increase in volumes sold.

Copper, lead and zinc sales increased by 22% to just under $1.6 billion, with copper accounting for $1.4 billion of the total, up 24% on the previous year.

The government attributed the overall increase in base metal sales to Sandfire Resources’ DeGrussa copper-gold mine and the restart of the Paroo Station lead project.

Mineral sands sales fell by almost 16% to $756 million, salt sales increased 8% to $382 million, coal sales increased by 7% to $311 million and cobalt sales jumped 10% to $160 million.

Diamond sales volumes rebounded by 10.6% to 9.6 million carats, thanks to higher output from Argyle.

WA Mines and Petroleum Minister Bill Marmion said the figures, released by his department, showed the strength of the state’s resources industry.

“What this means is jobs, jobs, jobs for West Australians,” he said.

Marmion added that he was working with the Department of Mines and Petroleum to drive down costs and attract further resources investment into WA.

“Our state maintained its ranking in the Fraser Institute Survey of Mining Companies during 2012-13, achieving the highest ranking in Australia and the 15th best exploration destination in the world, which is impressive,” he said.

All up, mineral and petroleum exports accounted for 89% of the WA’s total merchandise exports, with China remaining as the state’s major trading partner, taking almost half of all merchandise exports.

According the Australian Bureau of Statistics, investment activity in WA grew by 7% to a record $48 billion in FY13, attracting 51% of Australia’s mining investment activity.

The DMP said WA had an estimated $146 billion worth of resource projects under construction or in the committed stage of development, with a further $97 billion identified as planned or possible projects in coming years.