The Blarney Stone. The Blarney Stone (Irish: Cloch na Blarnan) is a block of Carboniferous limestone built into the battlements of Blarney Castle, Blarney, about 8 kilometres (5 mi) from Cork, Ireland.or he is a pilgrim from the Blarney stone.. Echoing the supposed power of the stone, an Irish bard of the early 19th century, Francis Sylvester Mahony, added a number of (humorous) lines to Richard Alfred Millikin's . The Groves of Blarney  (right).