A 20sided die from Roman times. 
MAT 160 Mathematical Problems & Games

Index Syllabus Homework 
Suggested References:
There are many other problem books that you can find
in the library. You are not required to buy any of these books since we are
not going to follow a specific text closely, but it is useful to
have a couple of them as a reference. If you come across any others on
your own, please bring them to our attention.
Here is a good geometry puzzle which is accessible to anyone who knows how to compute the area of a triangle.
Here are 3 single Roman dice (first centuries AD), made of various materials, that were recently for sale on eBay. Do these dice satisfy the modern requirement that pips on opposite faces add up to 7?