I made this 11x11 Hex board one year ago, with steel nuts and ball-bearings. All the balls had a smooth and reflecting surface. I used hydrochloric acid with some of them, to darken them, and eliminate the reflecting layer. The total weight, incluiding all the balls and the board, is over 5Kg. Here are some high-resolution pics, taken with a Leica Digilux Zoom digital camera.

You may also wish to visit My POV-RAY Hex Board Gallery.