![Top curves](../../../../jsp/jahia/templates/GSL/gsl_templates/img/keystage3/main_top_grad.gif)
Granite, Mourne Mountains, County Down
![Credit: Norman Moles](../../../../webdav/site/GSL/shared/images/education_and_careers/RockCycle/RocksAroundBritain/Granite%20-%20Norman%20Moles.jpg)
Normally the crystals that make up granite - mostly quartz and feldspar with some mica - interlock tightly together, which is why granite is such a durable rock. In some places, however, bubbles of gas in the magma left pockets that became lined with beautiful crystals, such as smoky quartz, green beryl and colourless topaz - mistaken in the past for diamonds!
Granite: Mourne Mountains, County Down
![Mourne Mountains, County Down](../../../../webdav/site/GSL/shared/images/education_and_careers/RockCycle/RocksAroundBritain/Mourne%20Mountains.jpg)
![Bottom curves](../../../../jsp/jahia/templates/GSL/gsl_templates/img/keystage3/bottom_curve.gif)