X-ray photoelectron spectroscopy (ESCA) has been used to investigate the surface/near surface chemistry of several silicates with the sodalite structure. An earlier study has established that core level binding energies in purely siliceous sodalite are similar to those for silica but different from an aluminosilicate sodalite with Si/Al approximate to 1. Binding energies for the latter are similar to those for zeolite Na-A, but distinctly different from those for the sheet silicate kaolinate (both with Si/Al approximate to 1). Thus ESCA is sensitive to structural features as well as chemical composition. Solid-state NMR shows that blue and pink ultramarines with bulk composition Si/Al = 1.04 and 1.11, respectively, violate the "Loewenstein rule" which forbids the presence of AI-O-Al bonds. ESCA reveals that the surface Si/Al ratio of blue ultramarine is 1.20, which corresponds to positive shifts in core level binding energies. Pink ultramarine has an even higher surface Si/Al ratio and corresponding growth in its core lines. Core level peak positions for zeolite losod, a compact and highly aluminous (Si/Al approximate to 1.0) framework silicate, are very close to those for aluminosilicate sodalite and zeolite Na-A. The results are fully consistent with our arguments concerning ESCA chemical shifts in aluminosilicates.