Rocks like sandstone, formed from particles of other rocks, are called sedimentary rocks.

Here's why:

* Sedimentary rocks are formed from the accumulation of sediments (rock fragments, mineral grains, or organic matter) that have been transported and deposited by wind, water, or ice.

* These sediments then undergo lithification (a process of compaction and cementation) over time, transforming them into solid rock.

Sandstone is a great example. It's made from sand grains (which are small fragments of other rocks) that have been cemented together.