Fallen moai head and red scoria topknot at Ahu Akahanga on Easter Island (Isla de Pascua) (Rapa Nui), UNESCO World Heritage Site, Chile, South America

Fallen moai and red scoria topknots at Ura Uranga Te Mahina ceremonial site on Easter Island (Isla de Pascua) (Rapa Nui), UNESCO World Heritage Site, Chile, South America

The red scoria quarry at Puna Pau, a cinder cone on the outskirts of Hanga Roa, Rapa Nui National Park, UNESCO World Heritage Site, Easter Island (Isla de Pascua), Chile, South America

Moai with scoria red topknots at the restored ceremonial site of Ahu Nau Nau on Easter Island (Isla de Pascua) (Rapa Nui), UNESCO World Heritage Site, Chile, South America

Outer crater and the small scoria cone, Formica leo, Piton de la Fournaise, Reunion, Africa

Excavating volcanic Scoria rock from the Seydisholar cone for road building material, near Selfoss, Iceland, Polar Regions

Scoria depsoits quarried from the Seydisholar scoria volcanic cone being used for road stone to create a network of tracks for new holiday cabins near Selfoss in Iceland, Polar Regions

Excavating volcanic Scoria rock from the Seydisholar cone for road building material, near Selfoss, Iceland, Polar Regions

Kerio volcanic crater near Selfoss, Iceland, Polar Regions

Red scoria and moss the caldera of the Ljotipollur volcano Iceland

Red scoria and moss the caldera of the Ljotipollur volcano Iceland