Ever notice how elements play favorites with their cosmic distribution? Iron and aluminum are the periodic table's basic bros—practically everywhere in the universe. Gold thinks it's special until you realize there's 187,000 tons of it just chilling in Earth's crust. Meanwhile, francium and astatine are the ultimate hipsters of chemistry—so rare that if you collected all the naturally occurring astatine on Earth, you'd have less than a teaspoon! Francium is so exclusive that at any moment, there's only 30 grams existing on the entire planet. Talk about playing hard to get! These elements aren't just rare—they're practically mythical creatures in lab coats.