Pietra dell'Etna, from Mt. Etna, Catania, Sicily, Italy
Geological description:
Ignimbrite. A poorly sorted breccia with clasts of rusty-coloured medium grained crystalline rock, discrete crystals of altered feldspar, and ferromagnesian minerals, all in a very fine-grained hematite-bearing groundmass. There is a faint preferred orientation of the clasts.
Comments:
No.652 is very similar ignimbrite, but a bit darker in colour.