Black SandBig Island, Hawai'i, USA. The Punalu'u Black Sand beach is a unique and beautiful place in the south of the Hawai'i Big Island. The black sand is formed when volcanic lava flows into the ocean and it disintegrates when it gets in contact with the cold water: A beach of black sand is thus formed: unfortunately it lasts only a fleeting moment in geological terms, since the black sand is quickly washed away after few decades. This beach is surrounded by