Provided are embodiments of conducting a special core analysis (SCAL) of an identified subset of core samples. Embodiments include determining rock quality values for core samples extracted from a subsurface hydrocarbon formation, and determining static rock types corresponding to the core samples based on the rock quality values. For each of the static rock types identified, scaling the corresponding rock quality values to generate scaled rock quality values, and determining a number of subspaces (ns) for the static rock type based on the scaled rock quality values. For each subspace of the static rock type: identifying a number (k) of most similar rock quality values in the subspace; identifying a subset of the core samples corresponding to the most similar rock quality values identified for the subspace of the static rock type; and conducting a SCAL of the core samples of the subset of the core samples.