* Minerals: Rocks are made up of minerals, and different minerals have different colors. For example:

* Quartz can be clear, white, pink, purple, or even black.

* Feldspar can be white, pink, or green.

* Garnet can be red, brown, or black.

* Weathering and Erosion: Over time, rocks can be weathered and eroded, changing their color. Rusting, for example, can turn rocks reddish-brown.

* Impurities: Tiny amounts of other substances in the rock can also affect its color.

So, it's impossible to say what color a rock is without knowing its composition and history!