It said over 11 days in January, it processed 1,655 tonnes at a feed grade of 2.3g/t gold with a 91.6% total recovery.

Over the 28 days of February, it processed 9,666.3t at 2.2g/t with an 89.2% recovery.

The company said the material processed during ramp-up was from the Guayabito and Guaico mines' development stockpile and the grade was lower than what was expected over the life of mine.

A 2018 preliminary economic assessment estimated a head grade of 6.43g/t for the five-year project, which is expected to produce a total of 150,900 ounces at an all-in sustaining cost of US$803.20/oz.

"Recovery rates and concentration ratios are within the estimated design parameters for this phase and we will continue to optimise in the coming weeks," president and CEO Gonzalo de Losada said.

Antioquia Gold had opted to delay the start of production at Guaico in mid-2017 to explore for more mineralisation.

It was then hoping to start up Cisneros in the fourth quarter of 2018 after it was slowed by challenging weather conditions in the first of last year.

The company has expanded its project footprint, announcing last month it had agreed to acquire the neighbouring La Palma and Cantayús properties from Gramalote Colombia for $850,000, which included the elimination of a previously-agreed NSR.

It had acquired the adjoining Guadualejo property from Gramalote in August.

Antioquia Gold gained C$26.97 million (US$20 million) last year through a rights offering at 4.2c per share, with major shareholder Infinita Prosperidad Minera SAC taking part to result in an 89.9% stake in the company.

Under a forbearance agreement, Infinita said it would not demand repayment of various multi-million dollar demand and term loans until 12 months after the May offering.

Antioquia Gold had a working capital deficit of $66.3 million (US$49.6 million) at the end of September.

It shares gained 1c or 33% to 4c yesterday, a midpoint in its 52-week range of 1.5c-9.5c, to capitalise it close to $38 million.