flinty Synonyms

stony obdurate granitic flint stiff stern steely solid shingly severe ruthless rugged rough rocky unsympathetic strong tough silicon oxide rocklike rock hard rockbound unforgiving calloused unbreakable bouldered unyielding unfeeling unbending rigid relentless hardened hard grim forbidding firm dour cruel callous bouldery austere adamantine harsh heartless pitiless petrous pebbly merciless lithoidal lithic lapideous