A methodology for timing interventions made on the polychrome decorations of the façade of the Palace of King Peter I, the Royal Alcázar of Seville, Spain

New Insights into the Medieval Hispano-Muslim Panel Painting: The Alfarje Found in a Balearic Casal (Spain)

“…Observed with polarized light, the particles exhibit pleochroism typical of azurite. In Figure 3 b accessory minerals that usually accompany azurite, such as quartz, calcite, and clayey minerals, are also seen [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. Natural cinnabar (HgS) is recognized by the characteristic intense red-orange color of its particles, which also exhibit high relief, prismatic habit, and angular shape due to the crushing process, as shown in Figure 2 a–c and Figure 3 c [ 15 , 35 ].…”

“…The taste for bright and contrasting tones was popular, so high-quality pigments were often used. Some significant examples can be cited that confirm this: Qusayr ‘Amra in Jordan (Umayyad wall paintings, 8th century) [ 59 ]; in the Nasrid period (14th century), the Alhambra [ 20 , 22 ] or the Dar al-Manjarra al Qubra [ 19 ]; and in Mudéjar architecture the facade of the palace of King Pedro I [ 27 , 28 ] or the plasterworks and the alfarje of Courtyard of the Maidens, both in the Royal Alcázar of Seville, built between 1356–1366 [ 29 ]. The color palette used by these artisans consisted of red, green, yellow, blue, black, and white hues.…”

“…In the eleventh century, natural resins began to be melted in oils and applied hot, which provided rough surfaces [ 63 ]. Linseed oil and diterpenic resins have been identified in the Alhambra complex [ 20 , 21 ], in the oratory of the Yusuf I Madrasa, Granada [ 74 ], or the Mudéjar façade of King Pedro I, Seville [ 27 , 28 ].…”

“…The pigment is bound with a proteinaceous glue, which acts as an adhesive for the foil. In the Nasrid dynasty of the Hispano-Muslim period, the use of gold sheets on thin layers made with bole (earth pigment) was common [ 11 , 20 , 25 , 75 ], while, in Mudéjar art, for example, in the Alcázar of Seville, gold is applied with mixtion (drying oil with siccative pigment) [ 27 , 28 ]. Other materials, besides gypsum, were found just underneath the metal foils.…”

“…Mudéjar monuments, such as the Casa de Pilatos palace (Seville), have been analyzed by portable X-ray fluorescence (XRF), SEM-EDX, optical microscopy, μRaman, and μFTIR [ 26 ]. In the study of the plasterworks and the façade in the Palace of King Pedro I and different courtyards of the Royal Alcázar of Sevilla [ 27 , 28 , 29 , 30 , 31 , 32 ] optical microscopy, SEM-EDX, XRD, GC-MS, Raman, and FTIR spectroscopy were used.…”