This color contains the following pigments:
charred animal bone
carbon + calcium phosphate
C + Ca3(PO4)2 or C × CaPO4
Ivory Black is a cool, semi-transparent blue-black with a slight brownish undertone and average tinting strength. It mixes well with any color, and creates a range of dull greens when mixed with yellow. It has good properties for use in oil, can be slow to dry in oil form, and should never be used in underpainting or frescoing. Ivory Black is denser than Lamp Black.
Ivory Black is very lightfast and has good permanence, though it is considered the least permanent of the major black pigments.
Ivory Black has no significant hazards.
Ivory Black is a carbon based black first named as Elephantium, and described in the 4th century BCE as produced by heating ivory scraps in clay pots to reduce the ivory or bone to charcoal. The deviation in names is because the more expensive varieties of this pigment were made by burning ivory, and the less expensive ones by burning animal bone. In the 19th century, the name Ivory Black was finally permitted to be applied to Carbon Black pigments made from bone. True Ivory Black is rare in modern times due to the protection of ivory, and the synthetic variety produced today was discovered in 1929. Bone Black is produced as an industrial pigment.
Zinc White is the coolest white, and it has a cold, clean masstone and a slightly bluish tint. It has less hiding power and is more transparent than other whites. It dries slowly and is good for painting wet into wet and for glazing and scumbling. Zinc White is neither as opaque nor as heavy as Lead White, its covering power is not as good, and it takes much longer to dry. However, it does not blacken when exposed to sulfur in the air as Lead White does. It is very valuable for making tints with other colors. Unmixed Zinc White dries to a brittle and dry paint film that may crack over the years, so it is not good for frescoing. It is more transparent in acrylic form than Titanium White and is the most commonly used white with gouache. Chinese White is a version of Zinc White appropriate for opaque watercolor techniques.
Zinc White has great permanence and lightfastness.
Zinc White is moderately toxic if ingested and slightly toxic if inhaled.
Though historians are divided on who first isolated the element zinc, they agree that it was first suggested as a white pigment in 1782. Zinc White was accepted as a watercolor in 1834 and was called Chinese White due to the popularity of oriental porcelain in Europe at the time. Ten years later, a suitable oil form was produced. By the early 20th century, it had improved to the point where it was an acceptable alternative to Flake White.