It was in 1969 and Mick Taylor and had just joined the band after Ry Cooder left. In order to help Mick Taylor adjust, the Stones had many jam sessions with him. One of the "official" releases was "Metamorphosis". The others were bootlegged. Many of the tunes on the bootlegged versions would continue to be played throughout time. These bootleg collections appear on "The Trident Mixes". The real dates of these recordings are conflicting. They were recorded at Trident Studios.