The company said it had advanced a decline 16m underground and was well on track for first gold production from the site in the September quarter.

Doray managing director Allan Kelly said the underground progress was a key step in becoming the state's next high-grade gold producer.

"The completion of the open pit and transition to underground mining is another significant milestone for Doray, again met on schedule, and is the beginning of a new phase for the company," he said.

"While the open pit mining has been exciting in itself, within the next month or so, we will commence mining the high-grade Wilber lode from underground and this makes up the bulk of the deposit."

The first cross cut is expected to be developed at the Wilber lode 65m below the surface, or 25m below the bottom of the open pit.

Ore will be stockpiled for future treatment once the processing plan is commissioned in the September quarter.

Doray advised that the construction of the processing plant and other site infrastructure was progressing on schedule.

The project's ball mill has arrived in Fremantle and is expected to be transferred to site next week.

Shares in Doray were unchanged today at A50c.