Fortescue Metals Group's High Court challenge against the Fderal Gvernment's mining tax has been adjourned for a month.

Fortescue is arguing that the Minerals Resource Rent Tax contravened the constitutional right of the states to deal with their own assets and property in a manner that they see fit.

The mining tax is levied at 30 per cent on the super profits of iron ore and coal companies.

The iron ore miner will argue that the constitution prohibits taxes that discriminate against some states.

It will also argue that the MRRT curtails a state's ability to determine what royalties are imposed and restricts its ability to aid mining.

Justice William Gummow today adjourned the hearing to allow Fortescue to amend its statement of claim and the Commonwealth to reply.