We have studied the dissolution of superficially porous silica particles incorporating organic-inorganic hybrid coatings and bonded phases under a high pH chromatographic testing condition to explore the column failure mechanism. The cleavage of bonded phases is examined using carbon analysis. The dissolution of silica is quantified by two different methods, direct weight loss measurements and the analyses of HF-digested concentrated effluents by flame atomic absorption. Reasonably consistent results have been achieved. Based on the experimental results, mathematical models have been developed to elucidate the shell and core silica dissolution rates of the hybrid superficially porous particles under the testing condition. We have quantified the space created inside the particles due to core silica dissolution using the Coulter technique, applied the method to test the shell and core silica dissolution models, and achieved comparable results. We have correlated the core silica dissolution models with the corresponding chromatographic behavior, and determined the failure mode. In this work, we have also compared high pH stability among different hybrid chromatographic materials.