How to Construct an Igneous Artificial Rock

Granite with gray, peach and cream streaks and dots

Learning about geology gives kids a chance to learn about the earth and one of its plentiful and varied materials: rock. The term igneous comes from a Greek word for fire. According to Geology.com, igneous rocks develop from molten rock material. In addition to obvious volcanic rocks such as pumice and obsidian, igneous rocks include granite, diorite and basalt. Creating artificial rocks gives kids a chance to personalize the learning experience. Use artificial rock in dioramas, educational displays and competitions for the most realistic or unusual rocks.

Things You'll Need

• Smock or old shirt
• Newspapers
• Igneous rock specimens or pictures
• Bowl
• Water
• White glue
• Stick or old spoon for stirring
• Granite spray paint in 2 or more colors--or gloss black for obsidian--for an adult or older kids to use
• Flathead screwdriver

Instructions

1. Put on a smock or old shirt to protect skin and clothes from glue and paint.

2. Cover the work surface with newspaper and set out the supplies. Provide igneous rock specimens for the kids to work from.

3. Mix one part glue to five parts water. For a group project or to make several artificial igneous rocks, empty the bottle of white glue into the bowl and refill the glue bottle with water five times and add the water to the bowl. Use a stick or old spoon to stir the glue and water.

4. Crumple one or two sheets of newspaper with your hands and shape the newspaper ball into a rock. Flatten it or make the shape irregular; for example, make it smaller on one end and thicker on the other to give it a realistic appearance.

5. Tear newspaper pages in half. Tear the half-pages into 1-inch-wide strips.

6. Dip a strip of newspaper into the glue-water paper mache mixture and slide the strip between two fingers to remove excess glue. Wrap the strip around the igneous rock you made from wadded newspaper.

7. Continue adding strips of paper mache. Crisscross the strips over the previous strips as you apply them to strengthen the rock.

8. Allow the rock to dry for at least half a day. It may take longer for large rocks and in rainy or humid weather. Turn the rock after three hours so that the base dries.

9. Put down newspaper to protect the work surface in a well-ventilated area. Read the spray paint instructions and follow all cautions. Use the granite paint to spray paint the rock with a textured finish. Pry the spray paint lid off with a flat head screwdriver. Shake the can. Aim the nozzle at the artificial igneous rock. For a multicolor igneous rock finish, press down on the nozzle and spray small dots and stripes on the rock. Add one or more other colors with the same painting method. Allow the rock to dry for at least an hour.

10. Turn the rock over, paint the underside the same way, and allow it to dry.

Tips & Warnings

• Add a coat of clear spray paint to protect the finish, if desired. It will make the artificial igneous rock shinier.

• Provide poster paints and sponges to apply the paint for younger kids. Show them how to use more than one color at a time.

• Don't leave kids unsupervised with spray paint.

References

• Geology: Igneous Rocks: Pictures
• Geosociety: Fake Rocks

Resources

• Massachusetts Institute of Technology: The Solid Materials of the Earth's Surface