Processing of low-grade ore is underway and will transition to run-of-mine ore over the coming week as operations move to steady state.

Gold in circuit has started to build, with the first gold pour expected within two weeks, well and truly within the company's previously stated target date of mid-May.

Calidus managing director Dave Reeves said the start of processing less than five years since the company listed on the ASX was a major achievement.

"Despite the challenges faced in our industry during the COVID pandemic, we are pleased to have delivered Warrawoona on time and on budget," he said.

"As Warrawoona completes successful commissioning and transitions into steady state operations, Calidus is well positioned for future growth and delivering strong shareholder returns.

"We look forward to becoming Western Australia's next gold producer."

Warrawoona is set to produce an average of 90,000 ounces of gold per annum - peaking at 105,000oz - over eight years, at all-in sustaining costs of A$1290 an ounce.

The project has a post-tax net present value of $245 million, internal rate of return of 57% and a 15-month payback period at a gold price of $2355/oz.

Gold is currently trading at more than $2600/oz.

Warrawoona comprises one large low-strip open pit and an underground mine, as well as a conventional 2-2.5 million tonne per annum carbon-in-leach.

Calidus is also completing a definitive feasibility study on the nearby high-grade Blue Spec deposit, which could see production rise to 139,000ozpa.

Shares in the company closed at $1.02 on Friday, valuing it at $410.3 million. The stock started the year at 65c and has been re-rating ahead of first gold production.

Canaccord Genuity maintained a speculative buy and $1.15 price target.