A world map shows phosphate mining locations marked by green circles with "P h." Key areas include the U S, Mexico, Brazil, Venezuela, Morocco, Egypt, South Africa, China, and Australia. Major clusters are in the U S, eastern China, and northern Africa.
Phosphate Mines | 4.70–4.79 pH | 4.80–4.89 pH | 4.90–4.99 pH | 5.00–5.09 pH | 5.10–5.19 pH | ≥5.30 pH | Settled prior to 2500 BCE | Settled by 1200 BCE | Settled by 200 BCE | Settled by 400 CE | Settled by 800 CE | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 4 | ||||||||||||
| 51 | ||||||||||||
| 11 | ||||||||||||
| 2.2 | ||||||||||||
| 4.833333333333333 | ||||||||||||
| 2.6666666666666665 | ||||||||||||
| 1 | ||||||||||||
| 6.3 | ||||||||||||
| 3 | ||||||||||||
| 61 | 1.13% | 1.16% | 1.51% | 1.42% | 1.12% | 45.8% | ||||||
| 3 | 99.3% | 83.2% | 31.2% | 37.5% | 99.1% | |||||||
| 1 | 36.0% | |||||||||||
0.16.0