The copper price rocketed more than 6% on Friday leading a broad rally in base metals after good economic news in the US , growth stimulus in the EU and a global  stock market rally .

By early afternoon in New York spot copper was changing hands at $3.31 a pound or just under $7,300 a tonne, up 6.8% on the day in heavy volumes.

The red metal was also boosted by a weaker dollar, short-covering and a drawdown in London Metal Exchange warehouse stocks.

LME inventories – a good indicator of overall demand – have almost tripled since October 2012 to above 600,000 tonnes; levels last seen in 2003 on fears of a slowdown in China.

China is responsible for 42% of total global demand of 20.5 million tonnes and its infrastructure investment-led growth has been a major factor in driving the copper price. In 2003 copper was worth 75c a pound.

Copper is still down 8% year to date, but is up sharply from 18-month lows of $3.06 hit on Wednesday.

Anywhere below $3 a pound has huge implications for the industry – the marginal costs of most producers  are in the $6,000 – $7,000 a tonne range or roughly $2.75 – $3.15 a pound.

Copper has stayed at relatively lofty levels thanks to largely static supply in global markets for a number of years.

But a slew of new mines in Indonesia, Peru and Mongolia coming on stream and expansion at existing mines in number one producer Chile this year will result in a 6.4% jump in mine output the International Copper Study Group estimates.

Judging by Friday's move not everyone is convinced that the market is facing a  massive surplus this year.

Copper was the star performer but nickel also rallied, climbing to more than $15,000 a tonne, while zinc, lead and aluminum also managed gains.