Group theory is applied to the analysis of atomic shells to 1) understand better the many surprising and unexpected simplifications that occur when group labels are used to describe atomic states and 2) exploit that knowledge in constructing effective operators to fit experimental data more closely. This leads to a description involving quasiparticles which can be thought of as quarks. The work is applicable to the spectra of the rare earths and actinide elements and has applications to many other areas of physics.
