Cobalt-chromite green and chrome-tin pink pigments have been prepared from chromium extracted from leather shavings pro- duced as a waste product of the leather-tanning industry. The alkaline agent (NaOH, CaO, MgO, NH_4OH) used in the extraction process influences the nature of the final product. The effect of the NH_4OH:CaO ratio on the final product in the case of cobalt- chromite green was examined. The pigments obtained were characterized by FT-IR and X-ray diffraction (XRD). Colour mea- surements were compared with those recorded from materials prepared form pure Cr_2O_3. The leaching of Cr(VI) from the materials was examined by U spectroscopy.
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