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What does a hardened lava flow look like? This photograph is of the frothy top of a lava flow near the fissure 8 vent, on Kīlauea Volcano's lower East Rift Zone. The different sizes and abundance of bubbles in the surface texture create different colors of the lava, including the light brown and darker black near the boot (for scale). The shiny smooth surfaces are the interiors of larger bubbles that formed from many smaller bubbles merging together. USGS image by C. Parcheta.