Some years ago I found this in the garden, under several inches of soil. No doubt, some decades before, it was a child's alley -- a "marble." Almost all its paint was worn off when I found it. It has sat in the pencil drawer of my desk ever since.

Tonight I shone a flashlight up through a loupe on which the alley was balanced. I liked what I saw.

The amber colour is a result of the paint on the lower side.