We had a wonderful lesson yesterday thanks to Cap Hensley! We have recently been learning about mountains and volcanos with my students of the 5th form. And we had a chance to see and to touch OBSIDIAN – one of the glassy products of volcanic activity, formed by the rapid cooling of silica-rich lava. When Cap Hensley brought it to the classroom, the kids shouted: “It is LAVA!” Great hands-on experience)))