Salt glazed mug .... is by Helen Perrett

Not sure who made this, but it reminds me of Al Wheldale's work, except that the mark looks like an M.
This has been salt glazed, but has had a glaze put on as well.

Many thanks to Suzy Dunser for recognising that this mug was made by Helen Perrett at a Diploma throwing module taken by Duncan Shearer in 2009, then fired at a Peter Lange salt/soda firing the next term.
This is not her usual HP stamp.