Boron
Boron is a chemical element, number 5 on the periodic table.

Boron was needed by Tesnians to breathe. They could also survive in an oxygen-nitrogen atmosphere, but needed to breathe boron at least six hours a day. ()

In 2373 a runabout carrying Benjamin Sisko and Michael Eddington ran into a pocket of boron gas which made it rock violently. ()

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Elements
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