Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 1161 | Metric tons | NA |
| 2003 | 1674 | Metric tons | 44.19% |
| 2004 | 1700 | Metric tons | 1.55% |
| 2005 | 1700 | Metric tons | 0.00% |
| 2006 | 2600 | Metric tons | 52.94% |
| 2007 | 3224 | Metric tons | 24.00% |
| 2008 | 3600 | Metric tons | 11.66% |
| 2009 | 2347 | Metric tons | -34.81% |
| 2010 | 2095 | Metric tons | -10.74% |
| 2011 | 2927 | Metric tons | 39.71% |
| 2012 | 3000 | Metric tons | 2.49% |
| 2013 | 3000 | Metric tons | 0.00% |
