The underground gold and silver miner said it had "transformed" its capital structure, eliminating convertible debentures, reducing its debt to equity ratio and increasing its cash position.

It reported a net loss of $30.7 million for the June quarter, compared with a net income of $33.8 million a year earlier, primarily due to extinguishing its 2020 and 2024 debentures.

Its adjusted net income rose from $6.8 million to $8.2 million and it generated $11.2 million in excess cash flow during the quarter.

Adjusted EBITDA of $26.5 million took the first half total to $53.9 million, up 55% over the first half of last year.

Executive co-chairman Serafino Iacono said senior debt was half the level of two years ago at $93 million and operating success at its high-grade Segovia gold mine was driving free cash flow.

"Our first half 2018 operating and financial results reaffirm that we are seeing continuous improvement in production, adjusted EBITDA and free cash flow," he said.

"We can now step into a new era, one where we use our internally generated cash flows and our high quality assets to take this company to the next level as a cash-generating, mid-size Latin America-focused gold producer."

The company lifted its 2018 production guidance last month to more than 200,000 ounces of gold after reporting a third consecutive quarter of more than 50,000oz.

It now intends to take its Segovia operations "to the next level" and has earmarked close to $30 million for capital investment at the operation this year, including expanding the tailings storage facilities at El Chocho.

Gran Colombia noted gold prices had dropped in the first half of the third quarter to average US$1,233/oz. If prices remained at this level, it still expected to continue to generate positive excess cash flow but at a reduced level compared with the first half of the year.

Its shares, which were trading at C$1.40 a year ago, peaked at $3.45 in May and closed up 1.75% to C$2.32 yesterday.