London Metal Exchange (LME) prices were loosely held in ranges in nervous trading on Tuesday, as supply worries encouraged buying, while scaled-up selling capped bolder advances, traders said.
"Copper prices initially drove down on fund and producer selling before finding support, while aluminium had trade support early on and then hedge selling knocked that," a trader said.
"Trade selling knocked nickel from an early lift in Asian trading, and zinc saw some CTA (Commodity Trade Advisory) buying late on, while other metals were comparatively quiet."
Traders said that investors were also wary of taking short positions with a rash of labour disputes threatening supplies.
Strikes are already causing disruption to North American aluminium production, while Grupo Mexico subsidiary Asarco's US copper units may be hit by industrial action if pay talks scheduled for the week of August 16 fail.
The market was also wary ahead of further macro-economic data, including the state of the labour market in the United States, expected on Friday.
Copper was quoted at $2,807 a tonne, down from $2,815 at Monday's evening kerb close.
Aluminium was up $7 to $1,702, while nickel was down $250 at $13,650.
Lead and zinc edged up, while tin was untraded in the kerb, ending slightly down.