I was looking for an authentic British Pint and mentioned it in conversation with the owner of my local beer store( super nice guy) the other day I was in and he had one for me, no charge, obviously from a personal collection. It's etched "PINT" , Crown beneath the word, and the number 414 beneath the crown. From internet research I've been able to determine that it is the inspectors number, and located in Derbyshire England. There doesn't seem to be a wealth of knowledge or interest in numbered imperial pint glasses. I think it's pretty interesting stuff and I'd like to find out more. I did find a PDF list of hundreds of numbers and locations. Any collectors or inspectors out there who care to weigh in?
Crate and Barrel sells them and they have 568 on them. http://www.crateandbarrel.com/pint-glass-tumbler-with-crown/s480428
I googled ' Imperial Pint glass numbering and found an article entitled 'Pint Glass Numbers' which seems to give a definitive answer. Check out this website link to the article... https://math.colorado.edu/~rmg/pint