Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 300 | Metric tons | NA |
| 2004 | 300 | Metric tons | 0.00% |
| 2005 | 300 | Metric tons | 0.00% |
| 2006 | 300 | Metric tons | 0.00% |
| 2007 | 300 | Metric tons | 0.00% |
| 2008 | 300 | Metric tons | 0.00% |
| 2009 | 250 | Metric tons | -16.67% |
| 2010 | 230 | Metric tons | -8.00% |
| 2011 | 210 | Metric tons | -8.70% |
| 2012 | 200 | Metric tons | -4.76% |
| 2013 | 200 | Metric tons | 0.00% |
