Wierd price of Zinc april 19 contract

Has anyone noticed the huge price difference in Zinc Mini and Zinc Mega contract of April 2019?
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Can anybody explain? Can we make a postion like selling 1 mega and buying 5 mini?

Kindly note Zinc will be going to physically settle from April expiry. Because of the cost involved, the rate is different for March and April.
Kindly go through this link