There are three main types of rocks, sedimentary, igneous and metamorphic. Each type can be found readily in most parts of the world, one only needs to know where to look and how to identify them.
Sedimentary rocks are formed by layers of sediment collecting over time and hardening into stone.
The most common form of this type of rock is sandstone, which is found readily almost everywhere. Metamorphic rocks are those that were at one time one of the other two types, but due to heat, pressure or other outside forces their fundamental makeup has change, examples would be marble or shale.
Finally, we come to Igneous, these are rocks that have been formed when magma from volcanos cool, such as granite or pumice. In some areas this may be the hardest type of rock to find, however don’t get discouraged, if you cannot find one you can always purchase one online or from a craft store (that sells stones for polishing or jewelry).
During this experiment, you are going to discover which type of rock is most damaged when frozen. All stone will be damaged to some degree by being frozen in water, because the water makes its way into tiny fissures in the stone. Then when it freezes it expands, exerting outward pressure on the stone.
It is important for us to know how different stones react to being frozen, for instance you wouldn’t want to make the foundation of a building out of a stone that is going to crumble the first time it freezes.
- Sedimentary rock (sandstone or limestone)
- Igneous rock (granite or pumice)
- Metamorphic rock (slate or marble)
- Several water bottles (one to hold each type of stone)
- Access to a freezer
- Cut the top off each of the water bottles.
- Place a different type of stone into each of the bottles (be sure to label the bottle with the type of stone).
- Completely submerge the stones in water.
- Place the bottles in the freezer, allow 24 hours to ensure the water is completely frozen.
- Remove the bottles and let them thaw.
- Repeat the process, freezing each bottle 3-4 times.
- Record your findings, which stones were most damaged and what state are they in now?