ALL meanings of blue john
blue john
B b - noun blue john a blue or purple fibrous variety of fluorspar occurring only in Derbyshire: used for vases, etc 3
- noun blue john (Britain, Derbyshire) A semiprecious mineral, a form of fluorite with bands of a purple-blue or yellowish colour. 0
- noun blue john (US) Completely skimmed milk, sometimes soured. 0