Igneous Rocks
Classifying and forming
Igneous rocks are rocks formed by magma and lava. When classifying igneous rock there are three ways. These ways are by it's origin, it's texture, and it's mineral composite. Origin is the way that igneous rocks form by intrusive and extrusive. Extrusive rocks form by hot lava cooling quickly on the earths surface and intrusive rocks form when hot magma cools slowly and hardens in earth. Think of it this way intrusive mean in and extrusive means out.
Uses
There are many uses for igneous rock some uses are statues, building, pavement, tools, counter tops and many more uses.
Rock Types
Here I will tell some different types of igneous rocks. They are made of many different minerals. Some igneous rocks are rhyolite, pegmatite, porphyry, marble and many more.
Igneous rocks are rocks formed by magma and lava. When classifying igneous rock there are three ways. These ways are by it's origin, it's texture, and it's mineral composite. Origin is the way that igneous rocks form by intrusive and extrusive. Extrusive rocks form by hot lava cooling quickly on the earths surface and intrusive rocks form when hot magma cools slowly and hardens in earth. Think of it this way intrusive mean in and extrusive means out.
Uses
There are many uses for igneous rock some uses are statues, building, pavement, tools, counter tops and many more uses.
Rock Types
Here I will tell some different types of igneous rocks. They are made of many different minerals. Some igneous rocks are rhyolite, pegmatite, porphyry, marble and many more.
![Picture](/uploads/2/4/2/8/24281207/1391703088.jpg)
Pegmatite is a light-colored, extremely coarse-grained intrusive igneous rock. For a rock to be pegmatite it has to be make up of almost all crystals. Pegmatite rocks are kind of rare because we don't find them often. Also pegmatite has very valuable minerals in it.
![Picture](/uploads/2/4/2/8/24281207/5941589.jpg)
Granite is a coarse grained igneous rock often with a pink to reddish color. Granite is mostly made up of small crystals. Uses for granite are counter top, building material, and stauches/sculptures.
![Picture](/uploads/2/4/2/8/24281207/2840848.jpg?1391703105)
Pumice is volcanic glass filled with gas bubble holes. Many times pumice is thought to be a glass foam ( because that's what it looks like). Because pumice has so many holes , it's very light and can float on water. Pumice comes in many colors (the color depends on the iron in it). However the most commonly found is gray. Pumice has a glassy luster.
![Picture](/uploads/2/4/2/8/24281207/3716236.jpg)
Obsidian is an igneous rock made extrusive by lava. Also obsidian is a naturally occurring volcanic glass. Obsidian texture is extremely smooth. The luster of obsidian is glassy and greasy.
Want to learn a little more about obsidian click here!
Want to learn a little more about obsidian click here!