Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 5600 | Metric tons | NA |
| 2003 | 700 | Metric tons | -87.50% |
| 2005 | 6000 | Metric tons | 757.14% |
| 2006 | 8400 | Metric tons | 40.00% |
| 2008 | 8400 | Metric tons | 0.00% |
| 2009 | 7600 | Metric tons | -9.52% |
| 2010 | 7900 | Metric tons | 3.95% |
| 2011 | 7600 | Metric tons | -3.80% |
| 2012 | 10400 | Metric tons | 36.84% |
