SHANGHAI, Apr. 30 (SMM) – Caution dominated SHFE market on the last trading day before the May Day holiday. SHFE 1507 aluminum contract touched RMB 13,370/mt twice, but then fell back. Finally, prices ended at RMB 13,360/mt. Trading volumes were down 18,882 lots to 472,848 lots, and positions were up 2,898 to 145,866.