Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 1 | Thousand metric tons | NA |
| 2004 | 1 | Thousand metric tons | 0.00 % |
| 2005 | 0.990000009536743 | Thousand metric tons | -1.00 % |
| 2006 | 1.34399998188019 | Thousand metric tons | 35.76 % |
| 2007 | 1.25999999046326 | Thousand metric tons | -6.25 % |
| 2008 | 4.07499980926514 | Thousand metric tons | 223.41 % |
| 2009 | 2 | Thousand metric tons | -50.92 % |
