Since lithium is such a useful element for making batteries, and possibly, in future, nuclear fusion. It seems a shame that it's somewhat rare. Why is that? iirc lithium is the 3rd lightest element in the periodic table. Hydrogen, the lightest element, is the most abundant element in the universe, followed by helium. Helium, the second lightest, is not very abundant on earth because it is non-reactive and such a light gas that it can easily escape the atmosphere. However, you'd have thought lithium would be more common than it is. It's reactive so forms solids and can't escape. Aluminium is close by in the periodic table and there is plenty of that. Sodium is in the same chemical group (iirc) and there is also plenty of that.