Making Rocks: Ingredients
We cannot re-create the process by which rocks are formed naturally on earth, but
we can use materials to simulate the formation of rocks. For this activity we are
going to use minerals and other earth materials to make a sedimentary rock. The
rock will form by a process called cementation.
Materials for each group:
One plastic tray
One container with
 6 Tbsp clay
 4 Tbsp gravel
 2 Tbsp sand
 2 Tbsp talc
 ½ Tbsp salt
 ½ Tbsp alum
Sediments
One cup of water with
 2-4 Tbsp water
1 tongue depressor
1 of each mystery mineral per rock made
 Example: 4-rocks = 4 of each mineral, one per rock
Fossil materials: leaves, twigs, chicken bone, etc.
Directions:
 Gather the proper amount of each sediment material in your plastic container
 Using the tongue depressor, mix the sediments and add just enough water so
the mixture resembles cookie dough.
 Divide the mixture into 4 rocks
 Add and bury the mineral/fossil materials in each individual rock
 Mold the dough into a rock and place group rocks on a plastic tray
 Place the tray in an undisturbed location until you are ready to begin lesson 9
(rock dissection and identification). A warm, well ventilated area is best.
Adapted from DELTA Science DSM III