| Home |
| Rocks and Minerals |
| Shale |
| Hornfels |
| Diabase |
| Limonite |
| Greenstone |
| Rhyolite |
| Quartzite |
| Conglomerate |
| Limestone |
| Sandstone |
| Calcite |
| Quartz |
Quartzite |
| Quartzite is a hard metamorphic rock that was once crystals of sand. Now you can find it at higher elevations in Frederick County because it resists weathering more than the rocks that were once above it. Click here to read more about this rock in our county at Sugarloaf Mountain and Devil's Racecourse. |
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