There are lots of types of rock and each type has different properties and uses. For example, some are strong and hard but others are soft and sandy. Some rocks are harder than others. For example ...

There are over 5,000 known types of minerals. Just a few minerals make up most of the rocks we see, though: feldspars, amphiboles, quartz, olivine, garnet, micas, calcite, and pyroxenes.

A new study in Chile shows how small differences in rock type can drive large differences in erosion, vegetation, and river networks, illuminating the role of mineralogy in shaping landscapes.