Types Of Igneous Rocks
Learn about types of igneous rocks. Igneous rocks are among those types of rocks which are formed by cooling of molten rocks. These rocks are formed after solidification of the magma or lava. They are usually found underneath the surface of earth, they are formed deeper inside from the upper surface. There are more 700 types of igneous rocks which are divided into two major categories; volcanic rocks and plutonic rocks.
VOLCANIC ROCKS:
Volcanic rocks are among those types of igneous rocks which are formed through crystallization of volcanoes. They are found on the upper surface of earth and are cooled very quickly that is why they are very refined. They also referred as Extrusive Igneous rocks.
PLUTONIC ROCKS:
These types of igneous rocks cool and solidified beneath the surface of earth that is why they are also known as intrusive igneous rocks. They take time to lose its temperature and solidify. They are bigger in size and are not fine grained as volcanic rocks.
Volcanic and plutonic rocks are further sub-divided into many other forms on the basis of different components including chemistry, texture and mineral compositions which are discussed below.
Pumice
Pumice is among the volcanic types of igneous rocks which have a glassy structure and very light in weight. It seems like a glass filled with bubbled gas and looks like glass foam. Mainly it is grey in color, but it comprises of many different and beautiful shades.
Obsidian
Obsidian is also among the volcanic types of igneous rocks and has same glassy structure as pumice but doesn’t have bubbled filled gas. It is very sharp in nature and can cut the skin even at one touch. It comprises of black and dark brown color, and it is also known as snowflake obsidian.
Basalt
Basalt is among the volcanic types of igneous rocks which are found mostly in the areas where there is frequent lava flows including Hawaii. It contains an enormous amount of iron and maintains its black and brown color. It can change its color when exposed to air.
Rhyolite
They are very finely crushed types of igneous rocks which might not be seen with the human eyes. It contains high silica and has various colors. It might be available in grey, brown, tan, yellow, pink and other earthy colors. It is very similar to other type of igneous rock i.e. granite, which is just sprinkle around on the surface.
Granite
Granite is very beautiful and common types of igneous rocks and used widely for various purposes. It possesses pink and red color and looks beautiful when sprinkled on the earth surface. It is little rough in nature. It is widely used in kitchen slabs and floorings.
Pegmatite
It is among the plutonic types of igneous rocks which are very large in size. It is one of the largest rocks in the world. It is little similar to granite in mineral composition but also possess high rate of mica and feldspar.
These are some of the types of igneous rocks other might include gabbro, diorite and porphyry.