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This piece of granite contains crystals of quartz, feldspar, and mica. Click on the image to look closer at the mineral crystals!
Click on image for full size
Courtesy of Corel

Granite Rocks

Look at granite closely and you can see crystals of common silicate minerals such as quartz, plagioclase feldspar and orthoclase feldspar. In fact, granite is mostly quartz and feldspar crystals. It also may contain mica minerals or other dark-colored silicate minerals. Click on the picture to the left to take a closer look at granite!

Granite is the most common type of intrusive igneous rock at the Earthís surface. Since granite forms deep within the Earth, you are probably wondering why we have so much of it at the Earthís surface. Rocks that were once deep within the Earthís crust are transported to the Earthís surface by plate tectonics! Colliding continental plates thrust rocks that were once deep underground up to the surface.

Because granite is very hard, it often used to make buildings, kitchen countertops, tombstones, and sculptures.


Last modified June 17, 2003 by Lisa Gardiner.

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The Fall 2010 issue of The Earth Scientist, focuses on rocks and minerals, including articles on minerals and mining, the use of minerals in society, and rare earth minerals, and includes 3 posters!

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