The Zorn palette refers to a palette of colors attributed to the Swedish artist, Anders Zorn (18 February 1860–22 August 1920). It consists of four colors: yellow ochre, ivory black, vermilion and lead white. Today, modern artists have substituted cadmium red light for vermilion and titanium white for lead white due to concerns of toxicity but mostly because these two pigments are not readily available.
Natural Pigments changes that by introducing the Rublev Colours Zorn Palette. Now paint with the genuine colors used by Anders Zorn in his paintings. Each set contains one 50 ml tube each of Genuine Vermilion, Lead White, Yellow Ochre and Bone Black. (Lists of the black color on the Zorn palette identify it as ivory black, but most ivory black sold in the early twentieth century was actually made from bone char or bone black. See note below.)
Charles Ubele writes about the manufacture of ivory black oil paint on page 124 in Paint Making and Color Grinding:
While many in the trade do not make a distinction between drop black or bone black and ivory black, the latter, nevertheless, is, or at least should be, made from the waste of ivory in turning and cutting of ornaments, etc., but, as there would not be enough to go around for the demand of the trade, the manufacturers of ivory black make use of animal bones, selected especially for this purpose, especially the knuckles and shins of bovines, while ordinary bone black of extra fine texture and hue is also sold under the name of ivory black.
Charles Ludwig Uebele (1913) Paint Making and Color Grinding: A Practical Treatise for Paint Manufacturers and Factory Managers. Painter’s Magazine.