US STOCKS-Wall St down with materials, energy after reversing early gain
* Materials drag, led by Freeport McMoran
* Oil falls near 6-year low; copper sinks
* Indexes down: Dow 0.4 pct, S&P 0.5 pct, Nasdaq 0.3 pct (Updates to late afternoon)
By Caroline Valetkevitch
NEW YORK, Jan 13 (Reuters) - U.S. stocks fell in afternoon trading on Tuesday, reversing earlier gains of more than 1 percent, led by a drop in materials and energy shares as commodity prices fell further.
The S&P 500 around midday broke below its 50-day moving average, triggering selling.
Shares of Freeport McMoran Copper & Gold were down 6.9 percent, the biggest drag on the S&P 500. The S&P materials index fell 1.7 percent and was the S&P 500's worst-performing sector.
Copper prices dropped further below $6,000 per tonne to their weakest level in more than five years, while oil prices extended losses in U.S. afternoon trading.
"We're seeing commodity prices continue to go down, not only in oil but across the board. So it's this fear of lower commodity prices leading to global deflation which is leading this nervousness," said Peter Cardillo, chief market economist at Rockwell Global Capital in New York. Continuación...