Thanks,
Some of the pieces are pretty small all right. In a few the greatest dimension is the thickness (1/16").
Abbas, I’m using uncoloured reptile sand from the pet store on a cheap but powerful hot plate. It takes about a half hour to achieve heat and then needs to be backed off a bit. Shading takes place at around 600 degrees F.

The early bird gets the worm but its the second mouse that gets the cheese.