Commodities markets summary
Market watch top headlines
A summary of trading in key commodities markets overseas:
Oil closed above $US90 a barrel for the first time in two months as it tracked an upward move in US stock markets.
Benchmark crude for February delivery ended the day at $US90.13 per barrel, up 15 cents, on the New York Mercantile Exchange.
Brent crude, used to price international varieties of oil, dropped 16 cents to finish at $US110.20 per barrel in London.
Meanwhile, gasoline prices continued to drop, while natural gas prices surged more than four per cent.
Hopes faded for a pre-Christmas deal to avert the so-called fiscal cliff as budget talks in Washington reached a partisan standoff.
Without a deal, the hundreds of billions of dollars in spending cuts and tax hikes that will take effect could throw the US economy back into recession, economists believe.
Such a prospect would likely mean decreasing energy demand.
Oil was lower for most of the morning then moved higher as US stocks pushed into positive territory in the afternoon.
Base metals slid to a negative close on the London Metal Exchange, as concerns over the US fiscal cliff and the duration of the nation's easy monetary policy gave investors reason to lock in profits.
At the close of open outcry trading, LME three-month copper was down 2.0 per cent at $US7,770 a metric ton. The metal earlier hit a three-week low at $US7,735/ton.
Concerns over the so-called fiscal cliff have been weighing on appetite for risk-related assets, such as base metals, in recent sessions.
The relatively strong run by metals such as copper since mid-November may also be playing a part in the complex's tumble, as investors take the opportunity to cash in on profits.
Gold and silver slumped to their lowest prices in almost four months as investors cashed out in anticipation of higher taxes in 2013 on investment income from the precious metals.
Though tax policy is still a subject of negotiations between the White House and congressional Republicans, a set of new or increased taxes is due to come on line next year, including higher rates on returns from gold exchange-traded funds and physical bullion, and on general investment income for high-net-worth individuals.
Gold has settled lower for three consecutive sessions amid fading hopes for a federal budget deal to avert the automatic tax increases and spending cuts set to take effect in January.
The most actively traded gold contract, for February delivery, fell $US21.80, or 1.3 per cent, to settle at $US1,645.90 a troy ounce on the Comex division of the New York Mercantile Exchange, the lowest since late August.
Silver, which had held larger gains than gold after rallying in September and October, dropped 4.6 per cent.
About half of global silver production is consumed by industry, including in electronics, solar panels and photography, and the chance that the fiscal cliff would hamper growth in the world's largest economy has sent investors to the exits.
Silver for March delivery fell $US1.438 to settle at $US29.678 an ounce on the Comex, the lowest since August 22.