Connellite

Walking along the beach looking at the cliffs of metamorphosed basalt, we suddenly noticed streaks of this bright turquoise-blue in the rocks. Looking closer we noticed several of what looked like mine shafts. I did a bit of research on google and discovered something that I probably should have known - that this was a big tin and copper mining area for several centuries. There are some old photos of the bay where I was walking (Carbis Bay, where the G7 summit was held last year) which show it as a moonscape of mining despoliation and tall stone engine houses and chimneys. It's very difficult to imagine in a modern area of wealthy tourism. The bright blue colour is a rare copper-complex mineral called Connellite.