The company reported March quarter production of 85,885 ounces of gold, down from 99,509oz in the December quarter, but in line with expectations due to a change in the Gwalia mine sequence.

Gwalia produced 56,773oz, down from 62,835oz, while Simberi produced 29,112oz, down from 36,674oz, due to a drop in milled grade and a loss of seven days of production due to an illegal strike.

Despite the result, St Barbara has upgraded its full-year guidance to 375,000-392,000oz from 365,000-385,000, with Simberi's outlook boosted from 115,000-125,000oz to 125,000-132,000oz.

The company is expecting Gwalia to have a strong June quarter as the mine sequence remains in higher-grade sections of the orebody and the revised stoping front provides more available stopes.

Full-year group guidance had already been increased from 350,000-375,000oz to 365,000-385,000oz in January.

St Barbara's quarter-end cash position increased from A$216 million to $262 million after net dividend payments of $16 million and $4 million invested in ABM Resources.

"The strength of our operations is demonstrated by continued strong cashflow generation during an anticipated lower production quarter," St Barbara managing director and CEO Bob Vassie said.

"Our cash balance continues to increase while we fund our various growth projects, exploration, investments and dividends. The company is well placed to capitalise on any further organic or other opportunities to grow shareholder value."

The company will release full cost and cashflow details in its full quarterly report to be released in two weeks.

Earlier this week, St Barbara announced a $4 million investment in Western Australian gold explorer Duketon Mining for a 12.3% stake.

Credit Suisse is curious as to why St Barbara would move on Duketon when the junior's projects sit so close to fellow mid-tier gold producer Regis Resources.

"Duketon would need a substantial discovery to underpin the hurdle rate of establishing a mine site," CS said.

"Regis has sunk around $300 million in high quality infrastructure which could accommodate discoveries on Duketon ground."

St Barbara's move on Duketon follows similar investments in juniors Peel Mining, Catalyst Metals, and more recently, ABM Resources.

Shares in St Barbara rose by 0.6% to $4.055, valuing it at around $2.1 billion. The stock hit a 52-week high of $4.23 last week.