We have reviewed some experimental aspects of the υ-particle family and their relation to the standard description in terms of a system formed out of a quark and an antiquark. The nonrelativistic potential approach, first applied to the charmonium states, has been extended successfully to the bb system. Since these bb states have much heavier masses than those of the charmonium particles, they do offer the opportunity to observe with a higher resolution power various QCD effects. In particular, one has found that the υ direct decay into hadrons is best described by the QCD-predicted 3-gluon decay mechanism. Furthermore, detailed analyses of the hadronic jet structure in this υ decay strongly favour the QCD vector assignment to the gluon.