thanks Sue ....... your reply reminded me a little of the joke, for which the punch line is - 'it was, and she is'

shame I couldn't find the link I wanted - it was something to which I contributed a year or two back - but no matter since you've confirmed the op's thoughts.
have attached some pix of other Alum Bay 'bottoms', showing their typical recessed pontil scar, plus another pic of an iridescent piece which I've always called a jip, and was confirmed by Alan Green (ex Alum Bay) as definitely being theirs - not so sure it is though - perhaps I'm using too much imagination, but it did have a jip look to me.