Baja Mining dropped 37% on Monday on more than 15 times usual trading volumes, after announcing its Boleo copper-cobalt-zinc project in Mexico will now cost 21.5% more and that half its board has resigned.
World number one miner BHP Billiton on Monday bought five additional exploration plots near its giant Olympic Dam mine and expansion project, destined to become the world's largest open pit.
A shuttered mine in Michigan's Upper Peninsula is attracting some unusual publicity, with persistent rumours that the owners are considering growing medical marijuana.
"The quality of this relationship with China's largest importer of copper concentrates provides further evidence that there is considerable interest in the high grade massive sulphides being found by the emerging seafloor resource production industry," said Nautilus CEO Stephen Rogers.
Chile will not be able to keep mining for copper, gold and other minerals if the government does not address the country's pressing energy needs, a mining conference in Santiago heard this week.