The characterization of lignocellulosic biomass present in archaeological wood is crucial for understanding the degradation processes affecting wooden artifacts. The lignocellulosic fractions in both the external and internal parts of Moroccan archaeological cedar wood (9th, 12th, and 21st centuries) were characterized using infrared spectroscopy (FTIR-ATR deconvolution mode), X-ray diffraction (XRD), and SEM analysis. The XRD demonstrates a significant reduction in the crystallinity index of cellulose from recent to aging samples. This finding is corroborated by the FTIR analysis, which shows a significant reduction in the area profiles of the C-H crystalline cellulosic bands (1374, 1315, and 1265 cm−1) and C-O-C (1150–1000 cm−1). The alterations in the lignin fraction of aging samples (from the 9th and 12th centuries) were demonstrated by a reduction in the intensity of the bands at 1271 and 1232 cm−1 (Car-O) and the formation of new compounds, such as quinones and/or diaryl carbonyl structures, within the 1700–1550 cm−1 range. The SEM images of cedar wood samples from the 9th and 12th centuries reveal voids, indicating that the entire cell wall component has been removed, a characteristic feature of simultaneous white rot fungi. In addition, horizontal “scratches” were noted, indicating possible bacterial activity.

This work consists of a scientific documentation of the eighteenth-century Chiadma carpet, currently on display at the Dar Si Said Museum in Marrakech. It is the earliest known carpet in Morocco, an example of Morocco’s tangible cultural heritage, commonly known as “Zarbia”. The study included scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) measurements, optical reflectance, 3D fluorescence, surface-enhanced Raman spectroscopy (SERS), and confocal µ-Raman spectroscopy. Since the few studies carried out on the Moroccan antique carpet heritage have focussed exclusively on the artistic aspects, the aim of the present work is to apply an integrated and non-destructive analytical approach to characterise the dyes used and then provide response elements on the dyeing protocol adopted. The wool fibres analysed by electron microscopy showed a certain degree of degradation/tearing and the presence of some impurities, while EDS allowed the detection of mordants in red and yellow fibres. In terms of dyes, the analyses highlighted carminic acid from cochineal extract in pinkish red shades, flavonoids from weld or Daphne gnidium in yellow shades, and natural indigo from Isatis or Indigofera tinctoria in blue shades. Mixtures of yellow dye plants with either madder or indigo were present in orange-yellow and green colours, respectively. The non-invasive techniques allowed rapid and real-time analysis, but their specificity was limited in terms of tracing the dyes to their botanical origin, i.e. the yellow-dyeing plants on aged fibres. On the other hand, the study highlighted the mastery of natural dye processing and provided relevant data to support any restoration of this prestigious carpet, which has suffered from ancient, non-controlled indoor conditions.