0307 GMT - Rio Tinto achieved some very impressive cost control at its Pilbara iron-ore operations in 1H, says Barclays analyst Amos Fletcher. Cash costs of US$25.0/ton were 7% below Barclays's expectations and 5% below consensus, he says. "Pilbara unit cost inflation was -7.1% [year over year] in constant currency terms for 1H26--impressive considering external pressures in the period," says Fletcher. Diesel prices, for one, have been materially higher, he says. Fletcher says the key was strong productivity gains, which included stopping using some underutilized equipment. One risk to watch ahead will be the unionization of the workforce in the Pilbara, which could have a negative influence on volumes and costs for all producers there, he says. Rio shares are up 1.1% in Sydney at A$167.14.