Shipments of Australian iron ore to China have dropped 9.5 per cent in September, according to latest data revealed by the Hedland Port Authority.

Exports to the world's largest consumer of the key steelmaking ingredient registered at only 15.13 million tonnes in September, compared to the 16.72 million tonnes in August, Port Hedland authorities said.

Year on year, it was a flat registry of improvement.

China mostly imports its iron ore requirements from Australia.

Overall, Port Hedland shipped a total of 19.9 million tonnes iron ore in September, still down from August's 22.8 million tonnes as well as the 20 million tonnes recorded in September 2011.

Port authorities said 2.1 million tonnes were exported to Japan in September, compared with the 2.4 million tonnes a month ago. Shipments to South Korea were likewise down in September at 1.9 million tonnes versus 2.7 million tonnes in August.

Prices of iron ore are currently struggling in the world market. From over $190 a tonne in 2011, it sank earlier in September to a three-year low of $86.70 before gaining back above $100.

But BHP Billiton, the world's biggest miner, believed the skyrocketing prices of the key steelmaking ingredient had reached its zenith and will not be able to replicate again what occurred in 2011.

BHP Billiton is Port Hedland's biggest user, followed by Fortescue Metals Group.