Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2009 | 15667 | Metric tons | NA |
| 2010 | 44500 | Metric tons | 184.04% |
| 2011 | 117420 | Metric tons | 163.87% |
| 2012 | 110000 | Metric tons | -6.32% |
| 2013 | 48500 | Metric tons | -55.91% |
