Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 6934 | Metric tons | NA |
| 2004 | 2762 | Metric tons | -60.17% |
| 2005 | 3355 | Metric tons | 21.47% |
| 2006 | 6276 | Metric tons | 87.06% |
| 2007 | 37979 | Metric tons | 505.15% |
| 2008 | 3170 | Metric tons | -91.65% |
| 2009 | 3416 | Metric tons | 7.76% |
| 2010 | 2944 | Metric tons | -13.82% |
| 2011 | 5528 | Metric tons | 87.77% |
| 2012 | 4200 | Metric tons | -24.02% |
