Stepping stone molds can also be used to create beautiful wall plaques.  Plaster works well for indoor plaques.  for outdoors there are many other options besides concrete - Gardencast, Aquacast, Hydrostone.  These fine-grained, durable, fast setting mixes are all manufactured by US Gypsum and can be readily found in your local home improvement store. 

Decorative Wall Plaque Instructions:

  • Pour the mold 3/4" to 1" full of plaster, concrete, etc.  Shake to remove air bubbles. Note: If there's a certain location at which you wish to position the hanger, mark that position on the lip of the mold before pouring the concrete. 
  • Bend a 10-12" length of sturdy wire (a coat hanger works well) in the center to form a U.  Curl the ends.
  • Press the wire into the concrete with the U protruding above the surface 1-2" below the upper rim.  To prevent the U from sinking into the cement or plaster, ballast the wire with a small chunk of styrofoam.