Steps 16 - 18: Polish, seal, and wax

16) Remove the edge form and cut out the sink plug. Then begin polishing with wet-dry sandpaper, diamond pads, or solid aluminum-carbide blocks. Start with 100- or 120-grit abrasive and work up to 220 and then 440. If sanding ejects whole pieces of sand or other aggregate, delay this step for another day. Keep handy a pan of water and a sponge (preferably the type sold for masonry jobs) so you can keep the surface damp and periodically wipe away the slurry you will create. Stop sanding when you like the effect.

17) If you see gaps that you don't like, fill them with a paste of cement and water. Allow them to harden for a few days. Polish with wet-dry sandpaper.

18) Seal and wax the counter before you use it.