Producers of metals and other raw materials fell as the dollar strengthened against other currencies and central-bank officials exhorted legislators to enact a fiscal stimulus bill.
Federal Reserve Chairman Jerome Powell warned a recovery is likely to be uneven unless "there is support coming both from Congress and from the Fed," during his second day of testimony on Capitol Hill, emphasizing the unique "power of fiscal policy."
Lithium miners, among the hottest stocks in the raw-materials industry group in recent years, fell in the wake of Tesla Chief Executive Elon Musk comments about ample supplies of lithium in the U.S. for electric-vehicle needs.
"Tesla announced improvements to battery technologies that are likely to support electric-vehicle sales in the longer term, but also to reduce lithium usage and production costs," said analysts at brokerage Morgan Stanley, in a note to clients.
"They also announced their own lithium mine with a new, lower-cost and more sustainable process."
Shares of Albemarle, which produces lithium in Chile and Australia; Livent, which has a production site in Argentina; and the Chilean producer known as SQM all fell sharply.
Gold futures, which are particularly sensitive to moves in the dollar, fell again Wednesday, closing around $1859 an ounce, as the dollar's gains against a basket of other currencies reached about 2% for the month of September.
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