Most Atlantic coast beaches have white or tan sand because of its high quartz content. Quartz is one of the weathering-resistant common minerals, so when rocks are eroded, the quartz is left when everything else is gone. Much of the Atlantic coast inland of the beaches is sediment eroded from rocks even farther inland, so the beaches are receiving sediment that has already had other minerals weathered away. On the other hand, New England has more igneous and metamorphic rocks exposed at the coast, so the beaches there are rockier, and the sand may be darker, because it is from fresher material.