Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 4300 | Metric tons | NA |
| 2004 | 6727 | Metric tons | 56.44% |
| 2005 | 7233 | Metric tons | 7.52% |
| 2006 | 19822 | Metric tons | 174.05% |
| 2007 | 4904 | Metric tons | -75.26% |
| 2008 | 14910 | Metric tons | 204.04% |
| 2009 | 8169 | Metric tons | -45.21% |
| 2010 | 8512 | Metric tons | 4.20% |
| 2011 | 1056 | Metric tons | -87.59% |
| 2012 | 22750 | Metric tons | 2,054.36% |
| 2013 | 10000 | Metric tons | -56.04% |
