marker dye to catch a thief

[Fred]

Hi all,

I don't know if anyone will know what I mean but there used to be a substance invisible to the naked eye that you could get to coat objects so that if someone touched them it would put a dye on their hands that wouldn't wash off for a couple of days, it was used to catch thieves largely. Does anyone know what it might be called?

Thanks.

[Vødkäjéllÿ]

It's called Gun Residue I think...

[shazzbat]

Trouble is, the thieving bar stewards who nicked your telly can't be touched, because the poor darlings are unemployed, come from a broken home etc, so they get off, while you get sued for assault, mental anguish, stress, you name it.

Not that I'm an old cynic or anything :-))

Steve