Here's a close-up of the smooth ropy lava called "pahoehoe" (PA-HOY-HOY). This sample is from the Mauna Ulu flow near Chain of Crater's Road, one of the stops on the Volcanoes National Park tour conducted by Hawaiian Eyes Land Tours. The brown fibers in the crevices are called Pele's hair, ultrafine strands of glass formed in lava fountains. (By the way, this image makes a great desktop wallpaper!)