Among the largest underlying components of XLB, in trading today DuPont ( NYSE: DD) is down about 0.7%, Freeport-McMoran ( NYSE: FCX) is off about 5.5%, and Monsanto Company ( NYSE: MON) is lower by about 0.3%.

FORBES: Materials Fund Sees Strong Inflows -- Top Holdings MON, DD, FCX

Among the largest underlying components of CU, in trading today Southern Copper ( NYSE: SCCO) is down about 1.8%, Freeport-McMoRan ( NYSE: FCX) is off about 7.1%, and Rio Tinto Plc ( NYSE: RIO) is lower by about 5.6%.

FORBES: Investors Move Money Out Of Copper

Freeport produced 251, 000 pounds of gold in Q4, up 38.7%.

FORBES: U.S. And China Strengthening, Gold To Average $1,700 In 2013: Freeport McMoran