Input (grade 13): Ivory is little used today, but has been important since ancient times for making a range of items, from ivory carvings to false teeth, fans, dominoes, joint tubes, piano keys and billiard balls.
Output (grade 5): Ivory has been used to make piano keys, billiard balls, handles and small ornaments. Ivory has been used in artworks, such as carvings, since ancient times.