Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 24.3819999694824 | Metric tons | NA |
| 2004 | 23.3560009002686 | Metric tons | -4.21% |
| 2005 | 42.5919990539551 | Metric tons | 82.36% |
| 2006 | 16.1770000457764 | Metric tons | -62.02% |
| 2007 | 51.5499992370605 | Metric tons | 218.66% |
| 2008 | 83.8539962768555 | Metric tons | 62.67% |
| 2009 | 84 | Metric tons | 0.17% |
