The diversity of historical textiles make important questions regarding dating and provenance more complicated. Valuable information can be provided by the characterization of the dyestuffs, which can help put a given textile into a geographical and historical context and, thus, complement other sources of information. Up to now, most of the investigations for this purpose have been complex and invasive. Here, a non-destructive methodology based on fibre optics reflectance spectroscopy is suggested. First, we built a database using reference samples of yellow dyed wool in the 0.35 to 1 [mu]m spectral range. The recorded spectra were analyzed using a statistical treatment (principal component analysis, or PCA for short). Then, a preliminary test was carried out to validate this method.