The use of dye resists to produce differential dyeing effects (e. g., bright, undyed hair tips on a darker ground) is described. Details are given for the required differential coloring technique for producing the color effects of Grey Persian Lamb on Indian lambs, using impregnation with lead salts. In the next stage, yellow ammonium sulfide or sodium sulfide and sulfuric acid are applied to form lead sulfide on the fur hairs. If the amount of sulfuric acid is increased, the color developed on the fur hairs has a bluer shade. In the absence of sulfuric acid, the color is black. The tips are finally brushed or sprayed with H₂O₂-H₂SO₄ or with HCl to produce a white color. The chemical nature of the grey bluish-black lead compound formed was investigated; this may be a double salt of PbS and PbSO₄. The bluish color formed on the fur is deeper than the color formed in the test tube reaction; this suggests that the sulfur of the keratin may play a part in the production of the blue color. -- AATA