Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 20 | Thousand metric tons | NA |
| 2004 | 20 | Thousand metric tons | 0.00% |
| 2005 | 25.7999992370605 | Thousand metric tons | 29.00% |
| 2006 | 30 | Thousand metric tons | 16.28% |
| 2007 | 30 | Thousand metric tons | 0.00% |
| 2008 | 30 | Thousand metric tons | 0.00% |
| 2009 | 30 | Thousand metric tons | 0.00% |
