Blarney Stone
The Blarney Stone was a block of stone that was used in the construction of Blarney Castle in Ireland on Earth. Kissing this landmark was said to grant an individual the skill of flattery.
While inquiring on the function of the Stone of J'Kah, Captain Jonathan Archer wondered if being blessed by it was to give him good luck. Commander Trip Tucker, however, corrected Archer, telling him that he must be thinking of the Blarney Stone, or patting (a statue of) the Buddha's belly. (ENT: "The Andorian Incident")
When Miles O'Brien met his old captain, Benjamin Maxwell, in 2367 and told him that he learned a lot from his former commanding officer, Maxwell responded with "But you got that silver tongue by kissing the stone, right?" (TNG: "The Wounded")