It was recognized early on that the periodic table more or less fizzles out after ... Estimates suggest that there is only about 30 g of francium in the whole of the Earth's crust.

That’s why this periodic table clock really caught our eye. [gocivici]’s idea is a simple one: light up three different elements with three different colors for hours, minutes, and seconds ...

Gethin: Francium. That's not an element that you ... and are placed in the first vertical column on the left of the periodic table. All the Group 1 elements are very reactive, and all react ...