Goldman’s venture into Colombian thermal coal started with the $US200 million ($A256 million) purchase of the La Francia mine. In 2012 Goldman bought a neighbouring coal mine and associated railroad stake off Brazilian mining giant Vale for around $407 million – leading to the consolidated Goldman division called Colombia Natural Resources.

Contractor legal disputes, labour protests and various production suspensions have rocked the coal operations since 2013 while the downturn in coal prices hasn’t helped either.

A Colombian government environmental move to end the practice of barging coal out to bigger ships has also disrupted the logistics of CNR while the US Federal Reserve is looking at new restrictions on how banks can produce and store raw materials in the wake of a US senate review on potential conflicts of interest in these matters last year.

The Wall Street Journal not only revealed that potential sales talks are underway but provided some profit/loss figures for CNR.

“Goldman’s losses were offset by financial transactions it began making in 2012 that produced profits when coal prices declined,” the newspaper reported.

“Those wagers generated a gain of $246 million in two years, according to Goldman records. Nevertheless, the firm had losses of more than $200 million on the Colombian coal venture, according to people with knowledge of the matter.”