Don't know much about this mug. Bought as one of a pair (similar glaze, different design) with the one uploaded next to it. Unmarked, very heavy, 6" tall and 3" diameter at the top. Thick mottled blue glaze over initial thin brown glaze (brown inside apart from the drips inside the rim). Seller on ebay was in the UK and deals with British fine ceramics - though this may be a complete red herring. This design is almost a copy of the Westwood W-2 - but is significantly larger, has no handle and on a different 'neck'/pedestal. Hobbyist?