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How abundant is fluorine in Earth's crust?

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A labeled diagram of the periodic table entry for fluorine, showing its atomic number 9, symbol F, atomic weight 18.998, electron configuration, and indicating it is a halogen and a gas at room temperature. — fluorine Properties of fluorine.

Fluorine is not a rare element; it makes up approximately 0.065 percent of Earth’s crust. While it is somewhat more abundant in the crust than chlorine, it is typically distributed in very small quantities throughout various rocks. Because of its high reactivity, it is found in nature only in the form of chemical compounds rather than in its free state.123