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Dinosaur Dig

DIY Paleontology Kit: How to Make Dinosaur Eggs and Fossils

You can create your own paleontology kit to use with these fossil rocks. Here are some suggestions:
How do you make your own dinosaur fossil rocks?
  • 1/2 cup of brewed coffee (room temperature or cold) (You can use food coloring in water instead.)

  • 1 cup of used coffee grounds (or substitute with sand.(

  • 1 cup of flour

  • 1/2 cup of salt

Step 1: Add the coffee grounds, flour, salt and about half of the brewed coffee to a bowl and mix together. Add the rest of the brewed coffee in slowly, as needed, to form a slightly sticky dough

Step 2: Form the dough around your dinosaur and shape it to look like a rock. To make it look realistic, give it an uneven, or rough texture. You can also leave a part of the dinosaur sticking out if you’d like.

Step 3: Place your "fossils" out in the sun to dry.

Step 4: After the fossils have dried, let kids break them open with a rock or a small hammer.

Dinosaur Eggs (without coffee)

Make your own "crack-open" dinosaur eggs or rocks, hiding small toys inside for a backyard dig.

Ingredients:

  • 4 cups play sand

  • 2 cups cornstarch

  • 1 and 1/2 cups water (add liquid food coloring for color, if desired. Purple and orange mixed together makes brown.)

Instructions:

  1. Mix: Combine the sand and cornstarch in a large mixing bowl.

  2. Combine: Slowly stir in the water until you reach a crumbly but packable consistency (similar to wet sand).

  3. Hide the Dino: Take a handful of the mixture, place a small plastic dinosaur or toy inside, and mold the mixture into a compact egg or rock shape. Ensure it’s packed tightly with no cracks.

  4. Dry: Let it air dry in a sunny spot for 2 to 3 days, or speed up the process by baking in the oven on the lowest heat setting.

Salt Dough To Make Fossils:

Ingredients:

  • 2 cups all-purpose flour

  • 1 cup salt

  • 1 cup water

Instructions:

  1. Mix: Combine the flour and salt in a bowl.

  2. Knead: Gradually add the water and mix until a dough forms. Knead the dough for about 5 minutes until it’s smooth.

  3. Create Rocks: Roll the dough out to roughly 1/3 -inch thickness, and use a cup to cut out circle shapes.

  4. Stamp: Create fossil impressions by pressing dinosaur feet, bones, or toy figurines firmly into the dough, and then carefully removing the item.

  5. Dry or Bake: Let the dough air dry for 24-48 hours, or bake in a low temperature oven at 200° F (93° C) for 2 or 3 hours.

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