Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2005 | 5636 | Metric tons | NA |
| 2006 | 1084 | Metric tons | -80.77% |
| 2007 | 7612 | Metric tons | 602.21% |
| 2008 | 11758 | Metric tons | 54.47% |
| 2009 | 17247 | Metric tons | 46.68% |
