Heavy rare earth prices soared to new highs this week as China continued its clampdown on mining operations in the southern provinces, market sources told IM.Export prices for europium and dysprosium oxides have more than tripled since the start of June, adding to last week’s record gains, and are expected to continue their bull run in the coming weeks. Heavy rare earth producers, largely based in the south-eastern province of Jiangxi, have been slowing production as the Chinese government carries out inspections to enforce environmental and safety standards.“I...