Rubber
Each eraser 1" square
Mexico City, MEXICO

Generally, erasers are made of rubber but prior to using rubber white bread was used to erase pencils. In 1770 an English engineer Edward Naime created the first rubber eraser. Supposedly he picked up a piece of rubber on his desk instead of breadcrumbs and discovered the properties of rubber for erasing. Although, while it worked well, rubber as a material then was not practical as it did not age well. It was not until Charles Goodyear, of the tires and blimp, invented vulcanized rubber in 1839 that rubber erasers became common.