Italian energy company Eni has chartered Vantage Drilling's Topaz Driller jack-up drilling rig for drilling operations in the Adriatic Sea, offshore Montenegro.Under the contract announced by Vantage on Tuesday, the 2009-built Topaz Driller will provide drilling services for 180 days.Ihab Toma, the Company’s Chief Executive Officer, said: “We are very pleased to announce this contract with our client Eni for the Topaz Driller in Montenegro…