SHANGHAI, Jul. 21 (SMM) – SHFE 1709 zinc opened at RMB 22,715/mt today and then dipped to RMB 22,670/mt. With entry of longs, SHFE 1709 zinc strengthened and then hovered around RMB 22,870/mt. In the afternoon, SHFE 1709 zinc fluctuated around RMB 22,840/mt and closed at RMB 22,840/mt, up RMB 80/mt or 0.35%. Trading volumes on SHFE 1708 zinc decreased 117,000 to 505,000 lots, and positions decreased 4,950 to 266,000.