Do you like camping, collecting rocks, and curious about igneous rock facts? It doesn’t matter if your answer is yes or no, but for sure, you should take a look at this review, because we’re going to discuss cool stones!
Igneous Rock Facts and Its Origins
Igneous rock is actually named after the Latin Ignis, which means fire. This rock is a magmatic rock. Have you ever heard that this type of rock is one of the three main rocks on Earth? Wow, it is very old!
The siblings of this rock are metamorphic and sedimentary rocks. Igneous rock can be formed from lava or magma which undergoes a process of solidification and cooling over a certain period. Magma can come from the crust or the mantle that melts. Melting usually occurs because of at least one or more of three processes, including temperature increase, decrease, pressure, and change in composition.
The Interesting Facts
As magma cools, its atoms and molecules rearrange themselves into cold mineral grains. Then, it forms rock when new. Some other interesting facts include:
- These rocks are made of minerals that can help plants thrive. How beautiful our ecosystem is!
- Igneous rocks cover 95% of the earth’s crust. It is formed from beneath the earth’s surface or as lava.
- If it is below the Earth’s surface, these rocks are called intrusive rocks. Meanwhile, rocks that come from lava that cools on the Earth’s surface are called extrusive rocks.
- The characteristic of intrusive igneous rock is its arrangement of coarse-grained crystals. We can see the mineral crystals if we look at them. Let’s just take a closer look at a slice of granite. There will appear spots that are black, gray, white, and also a little pink. These spots are the mineral crystals that form igneous rocks.
- While rocks that are undergoing a cooling process or extrusive rocks experience faster cooling than intrusive rocks. The constituent crystals are so small that they are invisible to the eye. The speed of the cooling lava affects the types of extrusive rock that exist.
- Lava that cools and becomes solid means that it has undergone a crystallization process. The minerals that are formed into crystals get bigger the more they hit the other crystals. When more and more mineral crystals collide with each other, they cannot be separated anymore. Until finally it produces igneous rock.
- Igneous rocks that we can encounter in everyday life are granite. Usually, it is used to coat kitchen surfaces.
- Besides, igneous rocks also make up the formation of mountains. More and more igneous rock is found around the mountain, which means it can be said to be a volcano.
- The moon is also formed from igneous rock.
- 10. There are more than 700 types of igneous rock, including granite, pumice, basalt, and obsidian.
- Pumice has air cavities in it that are visible to the eye. It is formed when lava cools rapidly over the Earth’s surface. This pumice rock is so light that it does float on the surface of the water. However, actually, it is not a mixture of minerals but a kind of glass. Due to its light mass, it is often used as decoration. It can also be ground as an abrasive powder used in polishing compounds or even in soaps.
- Other igneous rocks facts is about Obsidian Rocks. It is also formed when lava cools rapidly above the Earth’s surface. It has sharp edges because it is also glass. In ancient times, this stone was used as the tip of an arrow and spear or a cutting knife.