This companies products are now very collectible and this patterned jug and shape is from their first range being 24,5 x 20 cm - 10" x 8" and has not been available for many years.  The range is tube lined where the pattern is made first by a raised border " similar to decorating a cake " then painted in bold colours being fired at least three times.This companies products are painted in bold colours being fired at least three times giving the chance of rejects every time..  This process very labour intensive making this type of product very expensive when made in the UK, yet the process was originally developed by the Chinese.