Commodities have surged, with many striking multi-month peaks after the Federal Reserve embarked upon new stimulus plans to boost the US economy, a major consumer of raw materials.
Global markets rallied after the Fed said on Thursday it would start a third program to purchase $US40 billion ($A38.10 billion) per month in mortgage-backed bonds - known more commonly as quantitative easing (QE3).
"As the Fed embarks on a third round of quantitative easing, risky assets are rallying hard," said Barclays Capital analyst Kevin Norrish on Friday.
The US central bank added that it would continue with the scheme until it saw substantial improvement in the jobs market. It also pledged to keep benchmark interest rates at ultra-low levels until at least mid-2015.
The news sent the euro soaring above $1.31 to a new four-month high. The weaker greenback boosts dollar-priced commodities, which become cheaper for buyers using stronger currencies. That tends to stimulate demand.
Analysts said dollar was being hit by the prospect of higher US inflation caused by the stimulus.
The euro also won a boost this week from German court approval for a new 500 billion euro firewall and fiscal pact, clearing a key hurdle in solving the eurozone debt crisis.
OIL: Prices hit four-month highs on news of more stimulus measures in the world's largest crude consuming nation, and on the back of ongoing geopolitical tensions in the Middle East.
Brent North Sea crude soared to $117.95 a barrel, touching the highest level since early May. New York's West Texas Intermediate (WTI) surged to a similar peak at $100.42.
"The Fed's announcement has caused crude oil prices to climb to multi-month highs," said Commerzbank analyst Carsten Fritsch.
While the announcement had been expected, dealers cheered the fact that the central bank said it will continue with the policy until it feels the economy is strong enough.
Crude futures also jumped higher in the wake of violent protests touched off by a film mocking Islam that was posted on the Internet.
Washington's ambassador to Libya was killed during a mob attack in the city of Benghazi on Tuesday.
Demonstrations have spread across the oil-rich Middle East and further afield, including to Bangladesh, Iran, Iraq, Israel, the Gaza Strip, Kuwait, Sudan, Tunisia and Yemen.
Added to the volatile geopolitical backdrop, traders remain deeply concerned over key crude producer Iran's nuclear ambitions.
By late Friday on London's Intercontinental Exchange, Brent North Sea crude for delivery in October leapt to $116.68 a barrel from $112.93 a week earlier.
On the New York Mercantile Exchange, West Texas Intermediate (WTI) or light sweet crude for October rose to $98.87 a barrel compared with $94.81 the previous week.
PRECIOUS METALS: Gold surged to a six-month high on the back of the Fed stimulus, while platinum was propelled by fresh labour unrest in key producer South Africa.
"The gold price rose ... and looks set to continue its upward trajectory in the current economic climate as an increasingly inflationary environment in the United States is supportive of a strong gold price going forwards," said Westhouse Securities analyst Rob Broke.
Gold is seen as a good hedge against inflation and also takes on a haven status in times of economic unrest.
The glamorous metal raced as high as $1,778 per ounce, which was the highest level since February 29. Silver meanwhile jumped to $34.94, last reached in March.
At the same time, platinum soared to $1,715.12 an ounce - also last seen on February 29.
The world's number four platinum producer Aquarius Platinum on Friday halted operations at a South African mine as rising unrest also forced top ferrochrome company Xstrata to shut down a chrome plant.
Police used stun grenades to disperse 1,500 protesters who had gathered at Aquarius and arrested seven people after the government announced a crackdown on the growing labour troubles.
By late Friday on the London Bullion Market, gold surged to $1,775.50 an ounce from $1,728 a week earlier.
Silver soared to $34.71 an ounce from $32.22.
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