He fought to keep criminal charges against him secret but former NSW mining minister Ian Macdonald has been revealed as the second Labor identity charged over a multimillion-dollar coal deal at the centre of an explosive corruption inquiry.

Fairfax Media previously revealed that Eddie Obeid and his entrepreneurial middle son, Moses, were quietly charged last year over a $30 million coal deal involving their family property at Mount Penny in the Bylong Valley.

Secrets revealed: Ex-NSW mining minister Ian Macdonald charged over lucrative coal deal. Credit: Nic Walker

The charges were suppressed to ensure Obeid snr, 72, suffered no prejudice in his recent criminal trial in the NSW Supreme Court over his business dealings at Circular Quay.

The former Labor powerbroker was convicted of misconduct in public office in June and the Crown is pushing for a jail sentence.