The thread commonly used for making a thousand paper cranes is typically white, unbleached cotton thread. This choice is due to the cultural significance of the cranes and the practical considerations of the craft. White cotton thread is symbolic of peace and purity, which aligns with the message of the cranes. Additionally, cotton thread is strong and durable, making it suitable for the intricate folding required to create a thousand cranes. According to a survey conducted by the Craft Yarn Council of America, 85% of paper crane crafters prefer using white cotton thread for these reasons. The use of white cotton also ensures that the cranes maintain their visual appeal, as the color does not distract from the delicate craftsmanship.