Non-ferrous metals have risen over the last week but percentage gains have been dwarfed by advances seen in major global mining company shares. "The severity (of the move) is quite uncommon. You only get these moves two or three times a decade," Birch said. "What we would like to see now is commodity prices moving upwards...and that would give even more confidence," he said in a telephonic interview.

Shares in British mining giant Rio Tinto Plc hit 1,073 pence on Monday, the highest since August 1997. Fellow FTSE-100 listed Billiton Plc hit 205p, having risen over 100 per cent from its early-September 1998 low-point. "We think the market for mining shares bottomed last August and it has been gradually improving since... What we have seen in this phenomenon of the last 10 days orso is the first major bit of sector rotation into the mining sector," Birch said.

A switch could be taking place away from the technology sector, now seen as overvalued, into undervalued cyclicals. "A lot of investors have low weighting in areas like mining, and they thought they would have time to consider their weighting.

A lot of people felt they would want to see metal prices moving decisively before they put money into this sector," he added. By comparison, underlying base metal prices, although higher, have not yet secured the stunning gains that would herald a sea-change in sentiment. On the London Metal Exchange (LME) copper prices hit a four-and-a-half month high of $1,563 a tonnes on Monday, up 14 per cent from the early-1999 21-year lows.

Aluminium prices are just under five-and-a-half month highs of $1,335, up 15 per cent from the low hit earlier this year. But this percentage gain is dwarfed by that of Billiton stock, which is heavily exposed to aluminium, and North America's Alcoa whichhas risen 90 per cent since last August.

Birch said that a move similar to that which occurred in crude oil prices recently would provide a significant boost to metal markets. Oil prices have risen some 68 per cent from lows just under $9.00 a barrel. "One needs to watch out for that type of move in the metals market.

If you did get it, I think that the mining sector would continue to do well, relative to the other parts of the stock-market," he said. Mercury Asset Management manages the Mercury World Mining investment trust, which has a worldwide portfolio of mining and metal securities.

MWM shares hit their highest levels since October 1997, although they are still at a discount to their net asset value. "We are pleased to see it...the mining sector fund has had a fantastic performance over the last few days," Birch said.