US copper futures fell almost 1.5 percent early on Tuesday on technical selling after recent rallies, and traders said the market could be poised for a deeper correction. Most active July copper on the New York Mercantile Exchange's COMEX division was down 5.0 cents to a session low of $3.5905 a lb by 10:25 am EDT (1425 GMT), after opening 0.45 cent up.
The session high was $3.6890. July copper had closed up 2.45 cents, or 0.7 percent, on Monday, overcoming early selling pressure, on underlying demand fundamentals, traders said.
"Right now, on the charts, it looks like its top heavy and maybe it's looking for another pullback," said a copper dealer in New York. Traders said prices in the longer term were still underpinned by demand from China, and that alone could help the market cope with any selling. Copper has seen a powerful bull market, with COMEX prices rising around 50 percent since the lows of February.
Much of the wind behind the rally has been China's insatiable need for raw materials for construction and infrastructure development. China's refined copper imports in March hit the highest level ever, with total imports exceeding 200,000 tonnes for the first time, data from China's customs bureau showed on Monday.