The source of almost all boron containing compounds is the mineral known as borax, which is composed of boron and oxygen, and termed a boron oxide. There are several naturally occurring minerals of boron oxide including tincal, colemanite, kernite, and ulexite.

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Importantly, borax (Na₂[B₄O₅(OH)₄]·8H₂O) must be transformed into a precursor for ammonia borane (NH₃BH₃), named sodium borohydride (NaBH₄). This is done through a series of chemical reactions whereby B(OCH₃)₃ is converted into NaBH₄ by reaction with NaH. The following chemical map indicates how green H₂ is incorporated into the ammonia borane product.

Although boron is present as 0.001% of the Earth’s crust, significant qualities are concentrated in particular countries across the globe. There is currently an estimated 1291712 tons or 1.29 x 10⁹ kg with Turkey owning 73.4% of the total reserve. Other countries with borax reserves are listed below.

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