Medieval Walls Contain Baked Bones

Medieval walls around Granada, Spain, contain animal bones to help strengthen them.

Archaeologists in Spain have determined that the purpose of a 14th century brick oven was to bake animal bones and mix them with other materials to produce a protective coating to strengthen the medieval walls of what is today Granada, Spain.

Ancient decorative and protective layers ~ or patinas ~ covering the outside of very old buildings have been subject of many analyses in archaeology, conservation and chemistry. Patinas have been a popular finishing for building exteriors and walls for aesthetic and protective reasons since ancient times.

“However, the results of this work are significant for archaeologists since this is the first report of burnt bones in a patina on a Muslim monument, as well as the archaeological artifacts ~ the oven and raw materials ~ used to produce them,” archaeologist Carolina Cardell told ScienceDaily.

Using a novel new method to identify the components of historical artifacts, the team found hydroxyapatite ~ the main component in bone pigments and animal bones ~ in the patina of Granada’s medieval walls. Their new test is inexpensive, identifies chemicals more accurately and does not harm the historical artifacts.

Click here for the ScienceDaily article.