Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 764 | Metric tons | NA |
| 2004 | 512 | Metric tons | -32.98% |
| 2005 | 510 | Metric tons | -0.39% |
| 2006 | 590 | Metric tons | 15.69% |
| 2007 | 232 | Metric tons | -60.68% |
| 2008 | 39 | Metric tons | -83.19% |
