CEO Brian Wesson said it was a major milestone for the rejuvenated company, which is yet to deliver a feasibility study for Otso.

The mine, previously known as Laiva, has had a stop-start history and last operated in 2019. 

"We look forward to continuing towards long term, sustainable commercial production over the following weeks," Wesson said.

Otso announced an updated resource in August prepared by the John T Boyd Company comprising a measured and indicated 527,200 ounces and an inferred 276,000oz.

It said at the time Boyd was preparing mine designs and a production plan which would form part of a feasibility study to follow.

Otso said yesterday it was currently processing about 4,000 tonnes of ore a day, blasting ore in mining areas four times a week, and ramping up towards nameplate capacity of 6,000t.

It expected to sell the first gold dore from site "over the next weeks".

The company raised US$5 million at 6c per unit last month in a placement to majority shareholder Brunswick Gold to fund the ramp up and for working capital.

Cyprus-based Brunswick had earlier invested $11 million at 5c per unit to fund the restart, giving it a 46% stake.

Lionsbridge Nominees and Pandion Mine Finance are Otso's other major shareholders with 13.4% and 12.8% respectively.

Otso shares (TSXV: OTSO) have spanned C3.5-10c over the past year and gained 25% to close at 7.5c yesterday, valuing it at $75.7 million (US$61 million).