In some cases the plastid disappears and the crystalline pigment only is left.
The composition of the pigment is quite similar to that of lapis lazuli; but the constitution of both is uncertain.
In addition to its brilliance, vermilion is a pigment of great intensity and durability, remaining unaffected by acid fumes.
The sulphur fires, and a fine blue pigment is obtained.
Most of the rubber now manufactured is not combined with sulphur when in the form of sheets, but is mechanically incorporated with about one-tenth of its weight of that substance by means of the mixing rollers - any required pigment or other matter, such as whiting or barium sulphate, being added.