Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 366 | Metric tons | NA |
| 2003 | 360 | Metric tons | -1.64% |
| 2004 | 400 | Metric tons | 11.11% |
| 2005 | 450 | Metric tons | 12.50% |
| 2006 | 450 | Metric tons | 0.00% |
| 2007 | 700 | Metric tons | 55.56% |
| 2008 | 700 | Metric tons | 0.00% |
| 2009 | 598 | Metric tons | -14.57% |
| 2010 | 925 | Metric tons | 54.68% |
| 2011 | 674 | Metric tons | -27.14% |
| 2012 | 762 | Metric tons | 13.06% |
| 2013 | 800 | Metric tons | 4.99% |