This paper describes a method to calculate confidence intervals for cu
mulative recovery and grade obtained from semi-batch flotation test re
sults. The method is based on the analysis of the propagation of measu
rement errors through the calculations. The advantage of using reconci
led data from material balancing over raw data is discussed, with refe
rence to results of semi-batch rougher flotation tests conducted using
a complex Cu-Pb-Zn ore. Copyright (C) 1996 Canadian institute of Mini
ng and Metallurgy. Published by Elsevier Science Ltd.