Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 9320 | Metric tons | NA |
| 2004 | 4473 | Metric tons | -52.01% |
| 2005 | 3808 | Metric tons | -14.87% |
| 2006 | 17176 | Metric tons | 351.05% |
| 2007 | 30234 | Metric tons | 76.02% |
| 2008 | 30000 | Metric tons | -0.77% |
