Bill Gates-backed mining company discovers vast Zambian copper deposit / Zambia rushes to rescue 7 trapped in Chinese-owned copper mine / Zambia mine: Chinese nationals among miners trapped in flooded shaft / First Quantum in talks with Jiangxi Copper on sale of stake in Zambian mines / Zambian mine disaster survivor found a week later, rescue efforts continue for dozens still missing / Rescuer raises hope of survivors at a Zambian mine where more than 30 have been buried for days / Zambian landslide: At least 7 miners killed, 20 missing after copper mine catastrophe