In the series they are currently filming,a chap comes in with a piece of glassware he paid a dealer 1000 quid for and is told its an olive oil bottle from tesco with the label steamed off!
Bbc have taken the decision not to show it to save him the embarrasement(shame)
Reminds me of a joke:
"Ive had a rummage in the loft and I found this-can you tell me what it is?"
dealer:"yes,its a water tank"