US copper futures rose to a one-week high early Tuesday, with support stemming from firmer tones in the broader base metals complex and concerns about supply tightness. Copper for September delivery was trading up 1.10 cents at $3.6920 a lb by 10:08 am EDT (1408 GMT) on the New York Mercantile Exchange's Comex division.
The morning range was from $3.6870 to $3.7450 which was its loftiest level since July 15. Technicians see support in September copper at $3.65 to $3.63 followed by $3.50 with resistance at $3.80, and then $4.00.