[willis936]

Why is it rare? Because it decays.

Why would anyone make a plan to use it as a fuel without a plan to generate it? They don't. You breed it in the blanket that collects the energy. The energy balance is quite positive.

[chasil]

And then, sometimes, you make it into keychains.

https://www.tecaccessories.com/collections/tritium-isotope-f...