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Granite

Granite is a hard rock that makes an excellent building or ornamental stone.

Granite rock from Dudley Museum

Granite

Granite is an igneous rock.

An igneous rock is formed directly from molten rock originating from within the Earth.

The different colours in the Granite are from the minerals making up the rock.

Granite is very hard and resistant to breakdown by weathering.


More about Granite

Granite is one of the most common rocks on Earth. It is resistant to weathering so often forms high Granite hills. For instance, Granite tors are a typical part of the scenery of Dartmoor in the southwest of England.

Granite is a coarse-grained rock. This is because it solidifies very slowly from molten magma deep underground. This slow cooling allows the crystals to grow large enough to be seen with the naked eye.

Although Granite is resistant to weathering, under the right conditions it will form quartz sand or break down to kaolin, or china clay. Kaolin is extremely economically important and is used in ceramics, paper making, toothpaste, cosmetics, porcelain and some medicines.

Granite a light coloured (leucocratic) rock with a felsic or acidic mineralogy, rich in silica. It is made up of glassy quartz, white brick-like crystals of plagioclase feldspar, pinkish crystals of potassium (or alkali feldspar) and some smaller dark minerals, typically biotite or hornblende.

Granite makes up the majority of the continents. It is less dense than ocean crust which is formed from basalt, so the granitic continents ‘float’ in the basaltic oceanic crust.

Granite usually forms large bodies called batholiths, which have a complex internal structure. Granite is often associated with the mountain building episodes of plate tectonics.


Want to know more?

To download this information or to find out more, click on the Resources to your right. 

This Granite is part of the collections held at Dudley Museum and Art Gallery. Use the ‘Dudley Metropolitan Borough Council‘ web link below to find out more about the Collections at Dudley.

 
Grey Heron from Birmingham Museum & Art Gallery

Herons are fish eating birds that are commonly seen along canals, lakes and rivers. To find out more about Herons, click on the image above.

 
 
Parkinsonia ammonite fossil cut in half from Wolverhampton Arts and Museums

Inside the shell of an Ammonite there are a series of wall making chambers. Find out more about this Sectioned Ammonite by clicking on the image above.