The $155 million cash deal was struck in August, with the remaining $65 million tranche to be delivered to the company before October 9, 2015.

Linc landed the royalty benefits when it sold the Carmichael acreage to Adani under a $500 million deal in 2010 with Adani agreeing to pay Linc a $2 per tonne royalty on future thermal coal from the tenement for the first 20 years of production.

While Linc once expected the royalty deed to provide a total cash stream of $3 billion, its CEO Peter Bond indicated at the time of the deal that the company was prioritising other opportunities such as further investment into its South Australian shale oil hunting subsidiary Sapex.

The Carmichael project is targeting 60 million tonnes per annum of export capacity.

Mining will involve the development of six open pits and five underground mines over 60 years, with the first surface operation planned for 2016 with a production rate of 5.5Mtpa.

Initial longwall production from the first underground mine is expected to reach 2.5Mtpa run-of-mine in 2018.