Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 10 | Thousand metric tons | NA |
| 2004 | 20 | Thousand metric tons | 100.00% |
| 2005 | 44.1220016479492 | Thousand metric tons | 120.61% |
| 2006 | 45.4199981689453 | Thousand metric tons | 2.94% |
| 2007 | 33.1349983215332 | Thousand metric tons | -27.05% |
| 2008 | 62.685001373291 | Thousand metric tons | 89.18% |
| 2009 | 27.636999130249 | Thousand metric tons | -55.91% |
| 2010 | 18.4479999542236 | Thousand metric tons | -33.25% |
| 2011 | 45.1870002746582 | Thousand metric tons | 144.94% |
| 2012 | 30 | Thousand metric tons | -33.61% |
