State-owned coal miner Solid Energy's plans to turn low-grade Southland lignite coal deposits into massive new industries make no sense and the coal should remain in the ground, says the Parliamentary Commissioner for the Environment.

Some top SOEs have been overvalued by their boards - with one worth just half its estimate, two new Treasury report say.

Rio Tinto Group, the world's third-largest mining company, has made a A$3.5 billion ($4.53 billion) takeover proposal for Riversdale Mining, which is developing coal mines in Africa.

Lord Hunt writes on the need to understand the Chinese policy on climate change.

The Pike River blast has led some miners to discuss whether it is safe to remain in the industry.

Grey District Mayor Tony Kokshoorn wants the mining industry to learn from past mistakes and has called for a royal inquiry.

The riches of the Paparoa Range were enticing, but the cost of extracting them was greater than anyone imagined, writes Grant Bradley

As the West Coast struggles with the emotional cost of the Pike River tragedy, chairman John Dow has reassured the community there is still a future for the mine and the company.

The only sign that the Pike River boss is feeling the strain are the dark bags under his eyes which sag lower by the day.

An Australian mine expert says there is no urgent need to reach the trapped miners "at this point in time", backing the Pike River rescue approach.

With luck, the country will receive news that the brave 29 are back above ground and telling tall tales over a beer.

Since its announcement in 2005, the Herald has tracked the progress of the Pike River coal mine.

Methane gas has long been identified as a potential problem for the Pike River Coal mine, as rescuers scramble to find up to 27 missing miners.

Send your messages of support to the families and friends of the trapped West Coast miners.