Think about using clay to make a silicone mold from for small cement items ;-)
A little Winter diversion that's a little off topic but fun to do on the kitchen table with your kids while hunkered down for the winter.
BAKER'S CLAY #1
1 part salt
2 parts flour
1 part water
NOTE: For a smooth clay use white flour and table salt. If you want a rougher texture as for; rocks, then use whole grain flour and kosher salt.
Mix and knead all the ingredients for about 2 minutes.
Shape the clay into desired shape.
Place formed clay on a foil-covered cookie sheet. (Prick larger areas with a tooth pick where it won't show.)
Bake at 275º Farenheit (or 140º Celcius) for about 1 hour or until golden and hard.
Cool and paint.
Preserve by spraying with clear varnish or acrylic sealer.
NOTE: You must seal item's made from flour based clays, or they will attract bugs and rodents.