Chemical analysis reveals origin of Pompeian mosaic tiles

Two Roman mosaics in the ancient city of Pompeii have been analysed by heritage scientists who used portable spectrometers to reveal what the different coloured tiles are made of. The materials they identified include reddish iron minerals and pieces of solidified lava from nearby Mount Vesuvius. The findings, the researchers say, will help ensure these 2000-year old artworks can be preserved in their original setting.