The Rock Recipe

We know what you are thinking. If you had your "druthers," you would probably prefer to see your favorite cherry chocolate birthday cake recipe on this page. After all, who wants to eat rocks? But before you get too disappointed, we will let you in on a little secret. You can eat the rocks you make using the recipe on this page. You will also learn a thing or two about rocks while you test and "taste" your rock recipe.

Let's review what you know so far about minerals. You know that there are more than 2,000 minerals found on Earth. You know that they are inorganic, solid and found in nature. You also know that each mineral has its own "recipe." Each mineral is made from certain combinations of elements. Also, these combinations of elements are arranged within the mineral. Sometimes these arrangements form crystals.

So what is the difference between a rock and a mineral? Do you know the answer? It is all in the recipe. Minerals are made from combinations of elements. Rocks are made from combinations of minerals. Let's pretend that one day you decided to make JELL-O® brand gelatin. It is not too difficult to make. First, you boil water, then you add the powder from the JELL-O® gelatin package and then add some ice. The JELL-O@ gelatin is made from one basic ingredient. Think of the JELL-O® gelatin as a mineral.

Plain JELL-O® gelatin is good stuff, but maybe you like your JELL-O® gelatin full of surprises. Do you like whip cream? Let's add some to you JELL-O gelatin. How about pineapple? Throw it in. Add as many ingredients as you would like to to your virtual JELL-O® gelatin. Think of each of these items as a mineral. Are you figuring out what you are making now? If you are thinking "rock," you are absolutely right. Rocks are combinations of minerals. Rocks are solids made of combinations of minerals. Minerals are the building blocks of rocks and rocks are identified by the minerals they contain.

MATERIALS: This is what you need.

• 1/4 cup of butter or margarine
• 40 large marshmallows
• 6 cups of Rice Krispies® cereal
• Various ingredients to represent minerals (raisins, nuts, M&M® candies, chocolate chips, Skittles® candies, etc.)
• Sauce pan
• Bowl
• Stirring spoon
• Hot plate or stove
• Cooking spray or butter to coat hands

1. Pour the cereal into a large bowl.
2. In a pan melt the butter and marshmallows over low heat.
3. Add the "minerals" to the mixture.
4. Wash and rinse hands and then coat them with butter or cooking spray.
5. Scoop out 1/2 cup of the mixture and press into a rock.
6. Repeat the above step until all of the mixture has been made into rocks.

Wait! Before you eat your rocks, answer the following questions:

1. Are all of the rocks exactly alike? Explain your answer.
2. Do some of the rocks contain more of certain minerals than others do?
3. Are some rocks larger than others?
4. If you were a scientist giving your rock a name, what would you call your rock? Explain your answer.

You have just been given two food examples of "rocks." Now it is your turn. Create your own rock recipe and record it below. You may even want to try making your rock at home with the help of your parents.