Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 800 | Metric tons | NA |
| 2003 | 800 | Metric tons | 0.00% |
| 2004 | 652 | Metric tons | -18.50% |
| 2005 | 668 | Metric tons | 2.45% |
| 2006 | 730 | Metric tons | 9.28% |
| 2007 | 750 | Metric tons | 2.74% |
| 2008 | 1465 | Metric tons | 95.33% |
| 2009 | 1719 | Metric tons | 17.34% |
| 2010 | 1603 | Metric tons | -6.75% |
| 2011 | 1620 | Metric tons | 1.06% |
| 2012 | 1500 | Metric tons | -7.41% |
