The Full Federal Court in Canberra ordered a stay on a determination made by the NNTT in June 2017, just days after the tribunal determined that ML04/459 could be granted, when the Mount Jowlaenga claimant group lodged an appeal.
The appeal was based on a technical argument in relation to the NNTT's interpretation of the time period for which Sheffield's negotiations needed to be assessed.
Sheffield has long said it expected to be vindicated, and did not expect the appeal would impact on Thunderbird's development timeline.
The NNTT ruling is independent of a non-binding deal Sheffield struck with the traditional owners last month that sets indicative key terms as a basis for a future native title agreement it hopes to finalise by November, once it agrees to a binding co-existence agreement, expected to be next month.
The traditional owners are expected to receive around A$100 million in royalties over Thunderbird's 42-year life, while Sheffield has set a goal of building to 40% Aboriginal employment within eight years of operations.
The company is now just waiting on a sign off from the Commonwealth.
Former environment minister Josh Frydenberg had been expected to sign it before the end of September, but with the Liberal National government's recent civil war disrupting the business of government that will now fall to WA MP Melissa Price, who was sworn in yesterday.
Thunderbird's first production is planned for 2020 based on a total resource of 3.23 billion tonnes of 6.9% heavy minerals and a higher grade area of 1.05Mt at 11.9% HM.
The company has kicked off a two-month regional drilling program ad a number of promising targets around Thunderbird that could serve as future feed for the planned plant.
Shares in Sheffield traded on yesterday at 90.5c, capitalising the company at $207 million.