The Fascinating World of Rocks
Humans Might be Hardheaded, but Planet Earth Is Made of Rocks
by Iron Lee, age 10
There are many different types of rocks. Some are smooth and shiny, some are rough and shiny, and some are rough and colorful. Besides their appearance, rocks are also different in the ways they are made.
Igneous rocks are made from heat. One way that they are formed is by hot molten magma from inside the earth that seeps out of volcanoes as lava. This lava cools and solidifies, creating rock such as basalt. It may also cool slowly underground forming big coarse mineral crystals.
Another type rock is sedimentary rocks. These rocks are formed under water. Underwater materials such as sand or mud can build up layers to create sedimentary rocks.
Metamorphic rock is another special rock. Metamorphic rocks are made from other rocks. When a rock is heated or squeezed this may change its minerals, creating a metamorphic rock. Marble is a type of metamorphic rock.
All rocks are unique and are made in different ways. Some rocks are worth a lot of money because they are rare or especially beautiful. There are many cool facts about rocks. The most interesting one to me is that they are made out of minerals.
[Source: The King Fisher Children’s Encyclopedia]