Calcium, The item will keep you alive
You're trying to survive on a wasteland planet?
It is a silvery metal like substance. Calcium is very important for your body's. Without the calcium you wouldn't be able to make for your bones, teeth, and shells fully. Calcium is the most abundant metal substance in your body. The metal is very difficult to ignite into a fire. The metal burns in air with a high-intensity orange and red light. Calcium metal reacts with water, generating hydrogen gas at a rate rapid enough to see, but not fast enough at room temperature to generate much heat. Calcium is a metal and located on period four group two.
Calcium has five stars in biological need because you need calcium to help make your bones and teeth. It only has one star for social because you probably wont want to trade it to other people because your body needs it to survive. I put two stars for defense because you can use it to make a fire to catch people on fire and put fire around you. Calcium has three stars in functional need because you can use the bones for weapons, tools, or structures. You can fend off bad guys with your bone sword.