"Infill ‘production control' drilling and detailed mine plan optimisation has resulted in a lower strip ratio (less waste) for the first two years of production, potentially reducing mining costs," the company said.
Mining of the open pits is set to start next month, which Strandline says is two months ahead of schedule.
Coburn has been projected to have average annual earnings of A$104 million and a plus-50% EBITDA margin.
The project is fully funded to production.
Shares in Strandline were down 1.5% to 32.5c in morning trade, capitalising the company at $403 million.
