Can anybody tell me what the size of this medal is and of which material it is made?

The answer is that the size of the medal is the projection that you see, or the size it appears on your computer screen. Although you imagine you see bronze, the material is actually digital matter.

From now on this medal exists also in your mind. So clearly it exists.

These images give the suggestion of a normal sized bronze medal, but all we are looking at are 0’s and 1’s. We are living in a digital era.

Welcome to the world of conceptual art.