Macmahon Holdings has reduced staff working hours, cut directors' pay and made another 40 people redundant under restructuring carried out to satisfy its bankers.

Shares in Mt Gibson Iron were firmer on a better than expected quarterly report from the iron ore miner and better sentiment towards the industry as a whole.

Directors and insolvency specialists are said to be working on a rescue plan for Viento Group after the contracting company was put into administration.

Shares in South Boulder Mines have been placed in a trading halt pending an announcement about a capital raising.

Troubled contractor Viento has entered administration a day after calling a trading halt in its shares to consider fresh funding options.

Shares in Sandfire Resources were higher after the company lifted both copper and gold production from its DeGrussa mine in the March quarter.

BC Iron is struggling to break even as weak prices forced the Pilbara miner to make deeper cost cuts.

Northern Star Resources says it has paid off its debts and is on track to meet production and cost guidance for the financial year, after another solid quarter at its Western Australian mines.

Workplace diversity remains the key to corporate success even through the challenges facing the resources industry, according to one of BHP Billiton's most senior executives.

Shares in Fortescue Metals Group have surged by more than 8 per cent after it raised US$2.3 ($2.96) billion in an oversubscribed bond offer.

Newcrest Mining has produced nearly 9 per cent more gold and received a near 12 per cent better price for it.