Tasmania's bauxite mine could eventually supply a potential production plant at Bell Bay.
Australian Bauxite Limited told the ASX on Thursday its Bald Hill Mine near Campbell Town had achieved a contracted export tonnage of 30,000 tonnes of cement-grade bauxite three weeks ahead of schedule.
"The ship's master and the customer's shipping department are investigating how to achieve a maximum tonnage shipment of 33,000 tonnes, subject to berth and tide conditions at Bell Bay Port during the late stage of loading," it said.
"Additional product stockpiles have been achieved, including fertiliser-grade bauxite, cement-grade bauxite and sizeable stockpiles of ALCORE refinery-grade bauxite.
"A sample of several tonnes of this refinery-grade bauxite will be supplied to the ALCORE Research Centre in Berkeley Vale, Central Coast, New South Wales, for refining into aluminium fluoride for potential customers to evaluate."
Bald Hill had potential to provide several years' worth of supply of ALCORE refinery-grade bauxite at marginal cost if subsidiary ALCORE Limited needed it for a Bell Bay production plant.
The mine had produced 31,600 tonnes for the export deal as of Monday.
Australian Bauxite had been required to produce 30,000-33,0000 tonnes of cement-grade bauxite before May 1.
It said the grades were better than specified in the contract, and that had been usual for its shipments to date.
Production at the mine would continue at least until the end of the week, when more than 33,000 tonnes would have been produced.
The company has other deposits in Tasmania, Queensland and New South Wales.