Now that we have gone through each part of the definition, it is time to put them all together. To do this, you will need that same materials you used for the previous parts of the definition:

As many of the items from the following list as you can:

• several mineral specimens
• several rock specimens
• coins, bone, teeth, sea shells, wood, nails, cloth, glass, feather, paper, water, salt, pepper, other objects made of different materials

Place all of the items on a flat surface.

Think back to the first part of the definition, "naturally occurring." We looked at this in minerals , and now again with rocks. Naturally occurring means not man-made, so remove all of the objects that were made by people. That rules out things like paper, cloth, bolts, pens, nails, etc.

"Solid" is the next part of the definition, so remove any object that is a liquid, gas, or plasma. This is where we remove the water.

The last part of the definition is that the substance has to form large layers or deposits in the Earth. That eliminates quite a few of the remaining items. You don't find large layers of wood, feathers, or quartz. The specimens that you have left can be considered to be rocks.