Producers of metals and other raw materials rose slightly after the Federal Reserve indicated it would keep pumping liquidity into financial markets.

Fed Chairman Jerome Powell said the path forward for the economy was uncertain and would depend on the course of the pandemic, and pledged that the central bank would provide support for as long as it took to stabilize the economy.

"The 'Fed put' remains intact since they do not have a handle with the course of the virus and whether lawmakers will not deliver enough fiscal stimulus," said Edward Moya, senior market analyst at foreign-exchange brokerage OANDA Group. The Fed's dovish posture further weighed on the dollar, driving up the prices of dollar-sensitive commodities such as gold.

Gold futures rose $8.80 per troy ounce, or 0.45%, to $1953.50, a fresh record high.

Rio Tinto reported a net profit of $3.32 billion in the six months through June, down from $4.13 billion a year earlier when it wrote down its investment in the Oyu Tolgoi copper deposit in Mongolia. The miner also boosted its midyear dividend payout, reflecting, in part, the increase in iron-ore prices. One brokerage said the materials sector has as much to do with earnings optimism as more closely followed sectors like technology.

"Interestingly, the inflection in the S&P 500 earnings [growth measure] is not being led by tech but by energy and materials," said strategists at brokerage Jefferies. "Meanwhile, the percentage of stocks with higher earnings-per-share revisions over the past month has come from health-care, financials, energy and materials."

Belgian chemicals processor Solvay posted a decrease in second-quarter net profit as the pandemic hurt demand in several sectors.


 Write to Rob Curran at rob.curran@dowjones.com