Location: Mauna Loa, Big Island, Hawaii
Pāhoehoe is one of the two types of lava emitted from Hawaii's volcanoes. Pāhoehoe comes out of the volcano as thick, syrupy, molten rock. Many different minerals are present in the lava in molten form. The temperature of the lava and its mineral composition act together to yield the color of the lava once it has cooled. Most cooled pāhoehoe is black or gray, but if you walk around an old lava field, from time to time you will come across a section that is colored red, ochre, or even blue.
We discovered this flat patch of pāhoehoe on an old (1935) lava flow from Hawaii's Mauna Loa volcano. As you can see, it has a rainbow of colors on it surface.