Around 1900 we had colored leathers and chrome tannage. Dyes included phospines, Bismarck brown and shading basic dyes, and acid and direct dyes e.g., resorcine browns, acid oranges, reds and yellows. Great change came with direct blacks and the control of color uniformity, pH and solubility. Modern lightfast dyes give uniform color over the pH range of chrome leathers, and dyes can be chosen for penetration and level dyeing. Pigment finishes appeared before World War I. Wartime shortages caused a return to dyewoods, e. g., hypernic, fustic and hematine, used with sumac, gambier, chestnut, etc. and strikers e.g., copperas, bluestone, sodium bichromate. Tanners soon resumed mordanting with extracts and dyeing with aniline colors for better depth, shade, feel and break. Dyes, dyewoods and strikers overtanned and embrittled leather, unlike many modern dyes. Black suede was diazotized and developed by 1910. Acid, chrome, direct and basic dyes were also used. In the 1930's, top buffing made color penetration crucial. The coloring of splits, and dyes used, is similar to suedes. Syntans, in wide use in the 1920's, bleach chrome-tanned stock, aiding white tannages , allow acid and direct dyes to give lighter shades with better penetration and uniformity, and are fine mordants for basic dyes.