Thurakzima 7

Thurakzima 7 was a planet which was visited by Eighth Doctor, who took Samantha Jones to an opera performed by the native silicon-based life-forms. (PDA: 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! (DWA: Signs of Life)