A little too easy to go for one of the myriad of Royal something Pottery, so will go for Ruskin pottery. Established by William Howsen Taylor producing experimental glazed decorative pottery. Including Souffle glazes, lustres, crystalline effects, but best remembered for his high fired reduction fired glazes in the style of the Chinese. Sadly he took is recipes with him to his grave - another slightly mad artist.
Uusally impressed marks, occassionally moulded.