Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 3531 | Metric tons | NA |
| 2004 | 9188 | Metric tons | 160.21% |
| 2005 | 15361 | Metric tons | 67.19% |
| 2006 | 17665 | Metric tons | 15.00% |
| 2007 | 16200 | Metric tons | -8.29% |
| 2008 | 6500 | Metric tons | -59.88% |
| 2009 | 7020 | Metric tons | 8.00% |
