Igneous is a type of rock. There are three main umbrella terms used to describe rocks: Sedimentary, metamorphic and igneous.
Igneous rocks are formed through the transformation of metamorphic rocks. The metamorphic rocks underground are heated to extreme temperatures by the earth's internal heat. These melted minerals are forced around the inside of the earth and over thousands of years will rise to the earth surface through a process called uplift; as they do so will cool and therefore harden into what we call igneous rocks. These types of rock take a very long time to form and are known to be the oldest type of rock.
The speed at which the magma is cooled results in different rock types within that one umbrella term of igneous. These sub types include: Granite, basalt, quartz, pumice and tuff amongst many others. These are some of the most well known of the igneous rocks. Igneous rocks can form both inside the earth (intrusive) and outside (extrusive). The process I mentioned earlier is the usual intrusive formation type; however some igneous rocks are formed outside the earth surface.
So how are these extrusive igneous rocks are formed? Well, mainly in volcanic eruptions. This speeds up the process of igneous formation significantly as magma is forced through the earth's surface through a point of weakness. This magma cools rapidly in comparison to that which forms underground and forms igneous rocks very quickly. The strength, beauty, and heat resistance qualities of this rock type mean it has all sorts of uses from kitchen benches to wall tiles.
Igneous rocks are formed through the transformation of metamorphic rocks. The metamorphic rocks underground are heated to extreme temperatures by the earth's internal heat. These melted minerals are forced around the inside of the earth and over thousands of years will rise to the earth surface through a process called uplift; as they do so will cool and therefore harden into what we call igneous rocks. These types of rock take a very long time to form and are known to be the oldest type of rock.
The speed at which the magma is cooled results in different rock types within that one umbrella term of igneous. These sub types include: Granite, basalt, quartz, pumice and tuff amongst many others. These are some of the most well known of the igneous rocks. Igneous rocks can form both inside the earth (intrusive) and outside (extrusive). The process I mentioned earlier is the usual intrusive formation type; however some igneous rocks are formed outside the earth surface.
So how are these extrusive igneous rocks are formed? Well, mainly in volcanic eruptions. This speeds up the process of igneous formation significantly as magma is forced through the earth's surface through a point of weakness. This magma cools rapidly in comparison to that which forms underground and forms igneous rocks very quickly. The strength, beauty, and heat resistance qualities of this rock type mean it has all sorts of uses from kitchen benches to wall tiles.