Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 477 | Metric tons | NA |
| 2004 | 489 | Metric tons | 2.52 % |
| 2005 | 409 | Metric tons | -16.36 % |
| 2006 | 457 | Metric tons | 11.74 % |
| 2007 | 583 | Metric tons | 27.57 % |
| 2008 | 599 | Metric tons | 2.74 % |
| 2009 | 610 | Metric tons | 1.84 % |
