Australia's miners fall to one-week low on soft commodity prices

** Australian miners index .AXMM falls as much as 1.2%, marking its lowest level September 18

** Sub-index tracks weakness is copper and iron ore prices MET/L IRONORE/

** BHP BHP.AX, Rio Tinto RIO.AX and Fortescue FMG.AX lose 0.7%, 1.1% and 0.3%, respectively

** YTD, AXMM up 13.4% vs benchmark's .AXJO 0.6% fall