To tie all the 'broken' pieces together, I used the Vallejo Oxide Paste, along with a variety of gravel and sand.

Adding those additional pieces to the sculpey texture really completes the look of the bases, especially the larger versions. This is a 60mm base.

This group shot shows a nice set of bases (for any number of game systems) which was created using one rolled out sheet of sculpey.
As I mentioned in the last post, I normally use the grey extra firm sculpey for these sheets. I didn't have any at this time, so I made do with the regular white sculpey.