Price in contracts

Hi,

Is it possible to maintain two price levels according to quality criteria for the same material in the contract? Example like this:

Cotton yarn is of 2 quality grade- grade A and grade B

Grade A quality material = 1000

Grade B quality material= 800

When I am making the PO referencing this contract, if I am ordering grade A cotton yarn the system should pick the price 1000 and when grade B the system should take 800.

with regards

Komal