Why is free bromine not found naturally in Earth’s crust?

Free bromine is not found naturally in Earth’s crust primarily because of its great chemical reactivity. As a member of the halogens, bromine is highly reactive and readily forms compounds with other elements, which is why it occurs in nature only in the form of soluble and insoluble bromides.12

Because of this high reactivity, bromine does not exist in its free, elemental state in the environment. Instead, it is found dispersed throughout the crust in combined forms or concentrated in sources such as ocean water, brines, and certain mineral deposits. Its chemical behavior is characterized by a strong tendency to participate in reactions, particularly with metals and other substances, which prevents it from remaining in a free state under natural conditions.123