Fears of a strike at the world's biggest copper mine along with shutdowns of oil refineries in Venezuela and the US added yesterday to the existing upward pressure on the prices of oil and other key commodities.
Copper for three months delivery jumped another three per cent, after rising nearly two per cent on Monday, to $7,380 a tonne.
This was largely a response to news that union leaders at Chile's Escondida mine said they would call a strike vote on Friday unless they receive an improved pay offer reflecting present-day copper prices. The Escondida labour contract negotiated in 2003, when copper prices were a fraction of today's, expired on August 2. There were also reports of production problems at another big Chilean copper mine, Chuquicamata.
Meantime, four separate oil refineries reported serious difficulties at the peak of the US summer driving season, while data showed Chinese demand for oil rose by 15 per cent in June.
In a market already nervous at the consequences of any spread of the conflict in Lebanon US light crude for August delivery rose another 37 cents to $75.37 a barrel. In London Brent crude for September was 34 cents higher at $74.95 at one time.
It later eased back to under $74 after Saudi Arabia pledged $1 billion to support Lebanon's economy.
Reports from Venezuela said its huge Amuay refinery, a leading supplier of gasoline to the US will be closed for up to eight months after a fire last week.
Separately, the US refiner Valero has shut its gasoline-m king unit at St Charles, Louisiana, and said it would cut output at another refinery in Memphis, Tennessee, for repairs expected to take nine days.
ConocoPhillips also announced a temporary shutdown at at refinery in Illinois, where cooling towers were damaged by a storm.
