By 1969 there was a clear rift between the two halves of Tyrannosaurus Rex. Bolan and his girlfriend June Child (ex-girlfriend of Syd Barrett) were living a quiet life, while Took had fully embraced the anti-commercial/community spirited/drug-taking ethos of the UK Underground scene centered around Ladbroke Grove. Took was also attracted to the most anarchistic elements, such as Mick Farren/Deviants and members of the Pink Fairies Rock 'n' Roll and Drinking Club.

By now Took was writing his own songs and wanted the duo to perform them, but Bolan firmly refused. Took contributed his talents and two songs, including "The Sparrow Is A Sign," to Twink's Think Pink album, which Bolan probably also did not approve of.

Bolan's relationship with Took ended after Unicorn, although they were contractually obliged to go through with a US tour which was doomed before it began. Poorly promoted and planned, the tour saw the acoustic duo senselessly billed alongside loud electric acts. Took commented that the audience often did not even notice they had started their set, and he would sometimes strip to the waist and whip himself in Iggy Pop manner.

As soon as he returned to the United Kingdom, Bolan replaced Took with bongo player Mickey Finn, who would remain with Bolan until 1975. They made A Beard of Stars, the final album under the name Tyrannosaurus Rex. Unlike Took, Finn had no song writing aspirations.

As well as progressively shorter titles, the albums began to show higher production values, more accessible song writing from Bolan, and experimentation with electric guitars and a rock sound. The breakthrough was in "King of the Rumbling Spires," (recorded with Steve Took) which used a full rock band. This era also saw the publication of The Warlock of Love, a book of Bolan's poetry; derided by critics, it nevertheless became the best-selling poetry book of its time.