Definitely so. The front looks way too lustrous because it appears to be a low-end AU. AU58 coins can look about as good as a MS64 or 65, but I say this would get cleaned w/ AU53 details.
This is an example of an inexperienced person messing with a coin that should have been left alone. The obverse shows heavy traces of toning that does not go away when you dip a coin to improve it. If the toning is too deep, you are much better off leaving the coin alone. Otherwise you get ugly streaks.
I thought as much - it was going cheap at an auction! I knew there was something wrong with it just by looking at it. I want to say the estimate was between £30-£50 roughly.
That is cheap given the amount detail that is left on the piece. That's $37.50 to $62.50 in U.S. dollars. The wholesale Good to VG price is $30 to $44, and pieces in Good don't look like much these days.
This piece is not only cleaned, but damaged, and would receive a Details Grade, if fortunate. There is nothing AU (or MS) about the piece.