1640s, from French granit(e) (17c.) or directly from Italian granito "granite," originally "grained," past-participle adjective from granire "granulate, make grainy," from grano "grain," from Latin granum "grain" (from PIE root *gre-no- "grain"). In reference to the appearance of the rock. Used figuratively for "hardness" (of the heart, head, etc.) from 1839. New Hampshire, U.S., has been the Granite State at least since 1825.