Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 197 | Metric tons | NA |
| 2003 | 192 | Metric tons | -2.54% |
| 2004 | 300 | Metric tons | 56.25% |
| 2005 | 140 | Metric tons | -53.33% |
| 2006 | 390 | Metric tons | 178.57% |
| 2007 | 740 | Metric tons | 89.74% |
| 2008 | 980 | Metric tons | 32.43% |
| 2009 | 2400 | Metric tons | 144.90% |
| 2010 | 3000 | Metric tons | 25.00% |
| 2011 | 2900 | Metric tons | -3.33% |
| 2012 | 1600 | Metric tons | -44.83% |
| 2013 | 1900 | Metric tons | 18.75% |
