HOME & GARDEN CONSUMER GUIDE
Rock On--Make Your Own Rocks and Fossils
If you have a kid living at your house who loves to get dirty and smash things, you will definitely want to try this activity. All you need to create your own rock recipe are a few household ingredients, some small treasures and a couple of hours. But first, brew yourself a big pot of coffee. You’re going to need it.While you are sipping your cup of joe, send your kids to gather up all those plastic trinkets they collect and can’t seem to part with. You’re going to need those too.
Materials:
- 1 ½ cups flour
- 1 cup used coffee grounds
- ½ cup salt
- ¼ cup sand
- 1 cup water
Treasure Rocks: Mix the ingredients together with a spoon in a large bowl until a soft dough forms. You may need to use more flour to get the consistency just right. Pinch off marshmallow-sized balls and lay them on a wax paper-lined cookie sheet. Carefully use your fingers to make a hole in each ball and then hide a small treasure inside. (See a list of ideas below.) If your trinkets are larger than will fit in the ball, you can use more dough but must allow for a longer drying time. Cover the hole and make sure the treasure is sealed in there really well. The rocks will shrink a bit as they dry so allow for a little extra space around the trinket.
At this point you can add glitter if you want to have a sparkly rock or paint carefully with acrylic or tempera paint to make it colorful. Let the rocks dry in a warm place for two to three days. If you don’t want to wait that long, remove the wax paper and bake for about 20 minutes in a 150-degree oven. (Special note: if you are going to bake your rocks, use food coloring instead of paint.)
Once the treasure rocks are cool and hard, kids can use a hammer to smash them open and reveal the prize. This gets a little messy, so it is a good idea to do it outside or on a newspaper-covered floor. And, of course, little fingers need special help using the hammer to make sure the rock is the only thing that gets smashed.
Treasure ideas:
- coins folded paper with a special note
- plastic figures or toys
- costume jewelry
- fool’s gold
- erasers
- small rubber balls
*You may want to wrap these things in a bit of plastic wrap or else plan on washing them well after they are freed from their dirty rock-homes.
Fossils: Another fun use for the rock recipe is making your own fossils. Mix the ingredients in the same way, but flatten the small balls into circles before drying. While the dough is still moist, firmly press your object into the dough and then remove carefully. Once the dough has hardened (or you’ve cooked it like above), you will have a really cool fossil of your very own making! If you want to hang your fossil from a string, make a hole in the dough along the edge before it dries.
Fossil objects:
- stiff leaves (bay leaves work well)
- dead bugs with hard shells
- small bones (like last night’s chicken)
- seashells
- plastic dinosaur models
- twigs
- bumpy rocks
These are great activities for birthday parties too. Use the treasure rocks for a pirate party and the fossils at a dinosaur bash. Or make some on your own and surprise your kids with an archaeological search in your back yard. If you use black paint, you may even want to fill a stocking next Christmas and surprise the recipient with treasure-filled “coal”.
Who knew coffee could be so much fun? Just use your imagination and rock on!

Susanna Hickman Bartee is an Army wife living with her husband and four children near Ansbach, Germany. She is the founder and editor of www.militarymama.net.