The Ishango Bone
In 1950 Jean de Heinzelin, a geologist from the Museum, led excavations on the Congolese bank of Lake Edward, near Ishango. In the ground he discovered this 10cm long bone, which is topped with a fragment of quartz and is nearly 20,000 years old.
What makes it unique are the notches that appear to be grouped together. On one side, for example, there are groups of three and six (2 x 3), four and eight (2 x 4), and five and ten (2 x 5) notches.
Take a look at the bone yourself and try to decipher it using the interactive display.