London copper eased on Friday from near a four-week top hit in the previous session but was still on track for the strongest week of gains since early March as signs of healthier Chinese demand buoyed sentiment, Reuters reported. Three-month copper on the London Metal Exchange slipped by 0.4% to $4,977 a ton, erasing small gains from the previous session when prices struck a four-week high at $5,065 a ton. Copper was on track to post a weekly gain of 3.6%, its largest since early March. Shanghai Futures Exchange copper was up 0.4% at 37,910 yuan ($5,849) a ton.