Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 5 | Thousand metric tons | NA |
| 2004 | 5 | Thousand metric tons | 0.00% |
| 2005 | 1.26300001144409 | Thousand metric tons | -74.74% |
| 2006 | 1.06500005722046 | Thousand metric tons | -15.68% |
| 2007 | 1.10000002384186 | Thousand metric tons | 3.29% |
