“3. United States
Mine production: 23 million MT
In 2019, US phosphate mining decreased, dropping by 2.8 million MT from the previous year. The top phosphate-producing states, Florida and North Carolina, accounted for over 75 percent of domestic output. The other 25 percent of US production came from Southeast Idaho and Utah.
The majority of the phosphate rock mined in the US is used for manufacturing phosphoric acid and superphosphoric acid. These types of wet-process phosphate products are used for things such as animal feed supplements. About half of this type of phosphate is exported in the form of merchant-grade phosphoric acid, granular diammonium and monoammonium phosphate fertilizer.”
Not only are there problems with phosphate, the world supply of potash is also questionable.
Monzanite sands are another source of Phosphate fertilizer as well as REEs (rare earths.)