Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 2900 | Metric tons | NA |
| 2004 | 3183 | Metric tons | 9.76% |
| 2005 | 2357 | Metric tons | -25.95% |
| 2006 | 3000 | Metric tons | 27.28% |
| 2007 | 3000 | Metric tons | 0.00% |
