Multidisciplinary study of glazed ceramics from Chamberí Metro Station (Madrid, Spain): A knowledge base with technological and heritage value

Abstract

Glazed ceramics -both original and replacement- from Chamberí Metro Station (built in 1919) in Madrid (Spain) were studied using a multidisciplinary approach aimed at finding out more about the materials and technologies used to make them. The original white tiles, which help illuminate these underground spaces, were manufactured in Onda, Castellón (Spain) with very calcareous clays fired at ≈950 °C and coated with lead alkali-glazes. The original decorative pieces, with a metallic sheen, were made in Triana, Seville (Spain) with calcareous and illite clays fired at temperatures of between 850 and 950 °C and treated with transparent lead glazes. The replacement pieces had the same appearance as the originals but were more resistant. The white tiles were made out of quartz-rich, illite-kaolinite and calcareous clays fired at temperatures of >950 °C with an alkali-glaze that was very rich in zircon and aluminium. The decorative pieces were made from illite-kaolinite clays very rich in aluminium and fired at <850 °C. These included an additive in the form of a highly refractory grog and were covered with an aluminium-rich lead‑potassium glaze. The manufacturing techniques used to make each type of piece varied depending on their particular function within the station.