Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 821 | Metric tons | NA |
| 2003 | 1003 | Metric tons | 22.17% |
| 2004 | 285 | Metric tons | -71.59% |
| 2005 | 922 | Metric tons | 223.51% |
| 2006 | 828 | Metric tons | -10.20% |
| 2007 | 437 | Metric tons | -47.22% |
| 2008 | 393 | Metric tons | -10.07% |
| 2009 | 572 | Metric tons | 45.55% |
| 2010 | 904 | Metric tons | 58.04% |
| 2011 | 633 | Metric tons | -29.98% |
| 2012 | 400 | Metric tons | -36.81% |
| 2013 | 400 | Metric tons | 0.00% |
