Other mistake: Near the end of episode 5, Stevens is reading out previous numbers of slave units and B.O.S.S is telling him the new ones. For New York, the previous figure was 7203 and the new figure 7580. However, for Moscow the previous figure was 10003 (ten thousand and three), and the new figure is 110098 (one hundred and ten thousand and ninety-eight), which is a big difference.
Revenge of the Cybermen - S12-E5
Other mistake: Shortly after the Doctor makes his speech to the Cybermen about how pathetic they are, you can see a Cyberman's head wobble.
Other mistake: In every William Hartnell title scene there is a point where it tells you that you are watching "DOCTOR OHO". It lasts for three seconds and is probably the result of a lazy FX team as the left side is a mirror image of the right.
The Talons of Weng-Chiang - S14-E6
Other mistake: When Li H'sen Chang makes his entrance at the Police Station in episode one he says "You seem remarkably well-informed, Doctor", despite the fact he has not been told the Doctor's name and no other character has referred to him as such.
Remembrance of the Daleks - S25-E1
Other mistake: Right before the Doctor gets attacked by the destroyed Dalek he says: "Let me see, Professor" but the subtitles says: "That's impressive."
Other mistake: In part one, one of the gunmen shoots at a bottle behind the bar and it takes several seconds for the bullet to travel only a few feet.
Other mistake: I know that regeneration causes the Doctor to change his appearance, but I didn't know it can produce a tattoo visible on the Doctor's right arm in episode 2.
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