How to Make Plaster Rocks

Like people, no two rocks are the same.

Landscape your yard with "rocks" made from plaster of Paris. These fake rocks are lightweight and easy to move around the yard. Plus, you can make them the exact size you need for your landscaping purposes.

Things You'll Need

• Nonslip shelf liner
• Assorted sized old stainless-steel or aluminum bowls
• Hammer
• Large mixing bowl
• 2 cups water
• 1/2 cup white glue
• Wooden spoon
• 4 cups plaster of Paris
• Craft paints in the colors brown, tan, black and grey
• 4 small bowls
• Sponge
• Scissors

Instructions

1. Lay a length of nonslip shelf liner on a table. Sit the metal bowls upside down on the nonslip surface.

2. Pound the sides and bottom of the bowls randomly with a hammer to make dented rock molds. Continue to hammer the bowls, making large and small dents until the bowls' outer surfaces resemble the naturally bumpy, uneven surfaces of rocks.

3. Turn the bowls upright and grease the inside and rim of each one with petroleum jelly using a paper towel to apply a thorough, yet thin, layer. The jelly will keep the plaster from sticking to the bowls.

4. In a mixing bowl, combine the water and glue. Mix well, using the wooden spoon.

5. Add the plaster of Paris to the water and glue mixture, 1 cup at a time, stirring after each addition.

6. Fill the greased metal bowls with the plaster mixture. Fill to the top for larger rocks or partway for smaller rocks.

7. Allow the plaster to set completely in the bowls.

8. Tip the plaster rocks out of the bowls while holding the flat side with one hand to keep the plaster mold from falling.

9. Place the plaster rocks right-side up on a clean work surface.

10. Pour a small amount of each craft paint color into four separate small bowls.

11. Cut the sponge into four pieces using scissors.

12. Dip a piece of sponge into one color and dab onto the rocks surface's unevenly. Allow the paint to dry. Repeat this process using a clean sponge for another color. Let the paint dry before adding the third and fourth colors to avoid smudging. For natural variation and differences in the rocks, layer each rock with colors differently, mix paint colors or allow the paint to smudge.

13. Allow the painted rocks to dry in a warm area.

Tips & Warnings

• Carefully scrap the flat-bottom plaster edges of your rocks by using a butter knife and rough sandpaper before painting your rocks. If reusing the dented bowls to make another set of plaster rocks, hammer the bowls again to create different shaped rocks. Use acrylic paints for a more intense color. If you will be placing your plaster rocks outdoors, apply a coat of clear, waterproof varnish over the dry painted surfaces using a paintbrush. Wipe the rocks' surfaces with dirt and attach bits of craft moss for a natural look.

• Some of the mold's dents may cause parts of the plaster to break off and remain inside of the bowl. This may enhance the naturally worn appearance of your rocks. But if you prefer, dig any broken parts out of the bowls and reattach them to the rocks where they belong using craft glue.

References

• FireHow: How to Make Extra Strong Plaster of Paris
• CraftIdeas.info: How to Use Molds to Make Plaster of Paris Castings