Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 189 | Metric tons | NA |
| 2003 | 145 | Metric tons | -23.28% |
| 2004 | 185 | Metric tons | 27.59% |
| 2005 | 185 | Metric tons | 0.00% |
| 2006 | 177 | Metric tons | -4.32% |
| 2007 | 137 | Metric tons | -22.60% |
| 2008 | 71 | Metric tons | -48.18% |
| 2009 | 86 | Metric tons | 21.13% |
| 2010 | 91 | Metric tons | 5.81% |
| 2011 | 92 | Metric tons | 1.10% |
| 2012 | 121 | Metric tons | 31.52% |
