Thurakzima 7

Thurakzima 7 was a planet visited by Eighth Doctor. He took Samantha Jones to an opera performed by the native silicon-based life-forms. (PROSE: The Janus Conjunction) The Tenth Doctor later mentioned the Living Stones of Thurakzima 7 as silicon-based life forms who put the "rock" into rock ‘n’ roll! (COMIC: Signs of Life)