Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 4000 | Metric tons | NA |
| 2003 | 4000 | Metric tons | 0.00% |
| 2004 | 4000 | Metric tons | 0.00% |
| 2005 | 4000 | Metric tons | 0.00% |
| 2006 | 4000 | Metric tons | 0.00% |
| 2007 | 4000 | Metric tons | 0.00% |
| 2008 | 4000 | Metric tons | 0.00% |
| 2009 | 4379 | Metric tons | 9.48% |
| 2010 | 4709 | Metric tons | 7.54% |
| 2011 | 6193 | Metric tons | 31.51% |
| 2012 | 6200 | Metric tons | 0.11% |
| 2013 | 6200 | Metric tons | 0.00% |
