Fig. 3

Photos of the larger fragments investigated in situ with DRIFTS (Frag1, Frag2) with the analyzed spots (White, Red, Yellow, BLack), and of the smaller ones found in the debris (Blue1, Blue2, Yellow, Yellow–Red, Brown, White, BLack) or scraped from the walls (Greyish, Red1, Red2). The relative walls are indicated in brackets