How to calculate for Aluminium and Zinc, parity and disparity between MCX price and International price?

As per SEBI guidelines, Aluminium contracts from the month of March 2019 and Zinc contracts from the April 2019 will be physically settled similar to Gold and Silver. Just saw this SEBI/MCX circular.

I can also see that MCX is now showing up a separate spot market price for these physically settled contracts.

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Now that these are physically settled, does someone have a calculation on how to calculate the parity/disparity between international price and local price of Zinc and Aluminium?

Can @nithin @MohammedFaisal @siva-reddy help?