Revealing mistake: When Ace and Susan are sitting underneath the huge pipe about to be executed by the Fondant surprise, it's obvious that the actresses aren't sitting directly underneath the pipe, but slightly behind it.
Revealing mistake: In episode one, as the Doctor is repairing the buggy, one of the patrol runs on too soon, realises that he's come in ahead of his 'cue', and runs back.
Revealing mistake: When the Doctor taps the ice crystals, they wobble instead of breaking.
Remembrance of the Daleks - S25-E1
Revealing mistake: When the Doctor slides with his umbrella from Coal Hill School to the Dalek spaceship, he is obviously not played by Sylvester McCoy. He is much too tall.
Answer: It was never destroyed on-screen; it was intact at the end of the TV movie, and destroyed by the start of the 2005 series. It was destroyed in the novel "The Ancestor Cell," but in a completely different manner to what happened in the series.
DaveJB