London copper futures rose 1.7 percent on Tuesday after a four-day weekend, lifted by steady performances by metals markets in Shanghai and New York, and zinc jumped 4 percent on signs of consumer buying. Copper for delivery in three months on the London Metal Exchange rose $130 to $7,970 a tonne at 0700 GMT. "Demand is still an easy story -- demand is healthy across Asia, but supply is more difficult to…