Two Metals Forge Ahead in Face of Commodity-Rally Fatigue

As the commodities bull market that started last month shows signs of fatigue, silver and zinc, this year’s best performers in the Bloomberg Commodity Index, are extending gains. Tightening supplies are helping boost the metals, buffering them from demand concerns that have sapped momentum in other raw materials. Silver output from mines will fall for the first time since 2011 this year, according to CPM Group, while analysts expect zinc production to trail demand.