On the basis of current knowledge only natural-colored wood species crafted to veneers were used for the decorative design of furniture and wooden interior in classical antiquity.First applications of artificially stained wood can be dated to the late Middle Ages. In the Renaissance wooden works of art were manufactured by using intarsia of natural-colored, fungus-stained and artificially stained veneers or wood shavings. The staining of wood with natural dyes and mordants for the manufacture of furniture, wooden relief intarsia, wood paneling and parquet floorings was perfected in the Baroque and Rococo period. Today the dyes and mordants of the marquetry have faded in most cases or the color of stained veneers has changed. Sometimes the original beauty can be seen on the reverse side of intarsia during restoration work. For the reconstruction of the original coloring it is necessary to identify the applied natural dyes and mordants and to compare the results with the historical recipes. Natural dyes can be analyzed by High Performance Liquid Chromatography (HPLC) with diode array detection or UV/VIS – Spectroscopy (UV/VIS). HPLC works rather precisely but requires a small sample, whereas UV/VIS is non-destructive method applicable in situ. However, thick layers of lacquers over the stained wood surface and strong decolorization hinder detection. The analysis of inorganic metal salts used for mordants can be carried out by determination of the elements with X-Ray Fluorescence Spectrometry (XRF) or Optical (Atomic) Emission Spectrometry (OES/AES). Mordant dyes and direct dyes such as brasilin (red) from brazil wood, berberine (yellow) from barberry, curcumin (yellow) from turmeric as well as the vat dye indigo (blue) from woad or the indigo-plant are often among those identified. Green colors were obtained using green-stained wood infected by fungi of the genus Chlorociboria or by means of mixtures with berberine and indigo. Tannins, in combination with iron salts, were applied to stain wood brown or black. The results are described on the basis of investigated wooden works of art.

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