Rocks are everywhere and their uses are many.

If all else falls, they can be used as weapons, heaters, building materials, tools – it is just about “you name it” and there is a function for the common rock; here are some common uses.

Sharpen your knife

Collect a palm-size river stone, spit on it, and drag your knife blade against it in a smooth, arcing motion away from you. Hold the blade at a 20-degree angle for maximum sharpness.

Split wood

Use a hardwood club to drive a large, wedge-shaped rock into a log.

Navigate

Pile stones into cairns to help ground crews positively identify your track.

Stay warm

Place larger rocks (softball- to football-size) in your fire and let them heat through.

Two cautions: Never use river stones—they might explode if heated—and don’t let the rocks superheat or they may accidentally ignite any woody materials around them.

To be sure, if you find yourself using a rock as a knife, you are in a situation that is dire.

But as a fail-back from your usual slate of survival tools, rocks can be a life-saver.

To learn more about how to use rocks as tools for survival, please check out Backpacker.