Synonyms for Granitic (same or very similar meaning)
WordNet sense 1 (showing unfeeling resistance to tender feelings):
flinty, obdurate, stonyWordNet sense 2 (lacking in feeling or pity or warmth):
hardhearted, heartlessWordNet sense 3 (hard as granite):
granitelike, rocklikeWordNet sense 4 (resisting weight or pressure):
hardFrom the ODE community, based on WordNetadd/edit