Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 8 | Metric tons | NA |
| 2003 | 8 | Metric tons | 0.00% |
| 2004 | 13 | Metric tons | 62.50% |
| 2005 | 12.8909997940063 | Metric tons | -0.84% |
| 2006 | 14.9060001373291 | Metric tons | 15.63% |
| 2007 | 12.3809995651245 | Metric tons | -16.94% |
| 2008 | 10.3879995346069 | Metric tons | -16.10% |
| 2009 | 8.23099994659424 | Metric tons | -20.76% |
| 2010 | 12.039999961853 | Metric tons | 46.28% |
| 2011 | 13.5240001678467 | Metric tons | 12.33% |
| 2012 | 13 | Metric tons | -3.87% |
