Chalk is a soft rock and wears away easily. This makes it ideal for making chalk sticks to write on blackboards. Other rocks, such as slate, do not let water soak through them. They are called ...
In the three other rock-carving areas there are softer rock types, and there has consequently been more erosion. But even in Kåfjord, where the red slate has more cracks than in the other areas, most ...
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