Shares of the Diamonds Trust ( DIA) ETF, which tracks the Dow Jones Industrial Average, fell 1% after Alcoa ( AA) and a handful of other Dow components slid lower Tuesday. Alcoa led the losers on the downside, with shares falling about 5% after the aluminum company posted disappointing second-quarter sales. Other Dow losers included Home Depot ( HD), which dropped 75 cents, or 2%, to $34.25; and Pfizer ( PFE), which slid 58 cents, or 2%, to $23.29. The Diamonds Trust was recently trading down 64 cents to $110.51. ETFs that follow the precious metals markets rose significantly Tuesday. The iShares Silver Trust ( SLV) jumped $4.66, or 4%, to $115.50. Shares of streetTRACKS Gold Shares ( GLD) rose $1.75, or 3%, to $63.77. The iShares COMEX Gold Trust ( IAU) ETF, meanwhile, tacked on $1.72, or 3%, to $63.87. A host of energy ETFs were trading higher Tuesday as crude oil prices climbed above $74 a barrel. The United States Oil fund ( USO) advanced 83 cents, or 1.2%, to $70.39, while the Oil Services HOLDRs ( OIH) rose $1.46 to $146.46. The Energy Select Sector SPRD rose 52 cents to $57.38. The iShares Dow Jones U.S. Energy ( IYE) ETF climbed 87 cents to $97.32. The iShares Goldman Sachs Networking ( IGN) ETF fell 1% after Lucent ( LU) warned that its third-quarter results would be below Wall Street's forecast. Lucent was recently trading down 14 cents, or 6%, to $2.20. Nortel Networks ( NT), another holding in the networking ETF, fell in sympathy. Nortel recently was down 15 cents, or 7%, to $2.09. The iShares ETF, meanwhile, was down 25 cents to $27.72.