Francium

chemistry · radioactive · alkali metal · ultra rare

Vanishes in seconds. Francium is so radioactive that its most stable form breaks down in just 22 minutes. This means scientists almost never get to study the same francium atom for very long because it keeps transforming into other elements.

Rarer than gold. There's probably only a few ounces of francium in the entire Earth's crust at any given time. It's the second rarest naturally occurring element, making it harder to find than gold or diamonds.

Super grabby metal. Francium is the second most electropositive element, meaning it desperately wants to give away its electrons to other atoms. Only caesium (another alkali metal) is greedier to lose its electrons.

Turns into other stuff. When francium atoms decay, they transform into astatine, radium, or radon. This happens so quickly that a chunk of francium is constantly changing into something else.

Alkali metal cousin. Francium belongs to the alkali metal family, which means it shares the same basic atomic structure as sodium, potassium, and lithium. It's like the wildest member of a chemical family.