Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 75 | Metric tons | NA |
| 2003 | 79 | Metric tons | 5.33% |
| 2004 | 79 | Metric tons | 0.00% |
| 2005 | 79 | Metric tons | 0.00% |
| 2006 | 25.2000007629395 | Metric tons | -68.10% |
| 2007 | 26 | Metric tons | 3.17% |
| 2008 | 28 | Metric tons | 7.69% |
| 2009 | 30 | Metric tons | 7.14% |
| 2010 | 30 | Metric tons | 0.00% |
| 2011 | 30 | Metric tons | 0.00% |
| 2012 | 28 | Metric tons | -6.67% |