1705 GMT [Dow Jones] - Comex copper closed sharply lower, with chart-based selling triggered as the July futures fell through their lows from the last two days. 'I really do think this is profit-taking,' says Catherine Virga, base-metals analyst with CPM Group. There may be some impact from softer housing data earlier in the week, but the severity of the decline suggests traders mainly booking profits after recent price gains, she says. 'I think we could have prices bounce back because of the potential strike in Peru,' Virga adds. After the close but ahead of settlement, July copper is down 10.05 cents to $3.5050 a pound.