Kelsey Centrifugai Jig 2.5 DO 90 100 Separa te Kelsey Centrifugai Jig testing of final tailings material containing ~ 1.4% Sn, from another operation, resulted in an upgrade of ~ 18: I to produce a relatively high grade ( ~25% Sn) concentra te ata tin recovery of ~45% anda corresponding mass recovery of ~2.5%.