Star sand beaches of japan - whats the secret behind this star sand ?

You don’t have to look to the sky to see stars in Okinawa, Japan—just visit the islands of Taketomi, Hatoma, and Iriomote, where star‑shaped sand sprinkles the beaches! The stars are actually the exoskeletons of tiny organisms known as Foraminifera. When Foraminifera die, their shells remain in the sea and are washed ashore by the tides.