Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 29 | Metric tons | NA |
| 2003 | 30 | Metric tons | 3.45% |
| 2004 | 30 | Metric tons | 0.00% |
| 2005 | 43.0029983520508 | Metric tons | 43.34% |
| 2006 | 27.2210006713867 | Metric tons | -36.70% |
| 2007 | 10.5679998397827 | Metric tons | -61.18% |
| 2008 | 18.2689990997314 | Metric tons | 72.87% |
| 2009 | 14.2639999389648 | Metric tons | -21.92% |
| 2010 | 17.1359996795654 | Metric tons | 20.13% |
| 2011 | 14.3240003585815 | Metric tons | -16.41% |
| 2012 | 5.62900018692017 | Metric tons | -60.70% |
