What are some atypical substrates you can sandcarve?

For sandcarving, we range from glass to stone and everything in between. Some other items that have worked well for sandcarving are: 

• Ceramic mugs
• Granite 
• Wood 
• Metal 
• Knives 
• Mirrors

Before owning a laser engraver, we even sandcarved iPads and MacBooks. We also like to blast aluminum before anodizing for a nice matte finish.

   —Glassmith2