permanent white
Noun
Meaning
permanent white (uncountable)
(chemistry) barium sulphate used as a white pigment or paint, in distinction from white lead, which tarnishes and darkens from the formation of the sulphide.
Noun
permanent white (uncountable)
(chemistry) barium sulphate used as a white pigment or paint, in distinction from white lead, which tarnishes and darkens from the formation of the sulphide.