Beat me to it. Francium and Cesium are not stable at all in a typical environment. Rubidium is VERY unstable as well...hell, even Sodium is reactive enough in pure form that it's not stable in mildly humid environments.You are not going to be able to buy Francium or Cesium for that matter. Francium is only found in man-made lab conditions for a split second, and Cesium is 1. too expensive in pure form, 2. rare in pure form, 3. not going to blow up only the boat, but probably everything around it in pure form.
at you.
I will come over and touch your boat for you.
It will explode into the internet!
No internet for you.