Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 4300 | Metric tons | NA |
| 2004 | 6727 | Metric tons | 56.44 % |
| 2005 | 7233 | Metric tons | 7.52 % |
| 2006 | 19822 | Metric tons | 174.05 % |
| 2007 | 4904 | Metric tons | -75.26 % |
| 2008 | 14910 | Metric tons | 204.04 % |
| 2009 | 10000 | Metric tons | -32.93 % |
