Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 10940 | Metric tons | NA |
| 2004 | 10050 | Metric tons | -8.14% |
| 2005 | 7590 | Metric tons | -24.48% |
| 2006 | 3028 | Metric tons | -60.11% |
| 2007 | 6154 | Metric tons | 103.24% |
| 2008 | 753 | Metric tons | -87.76% |
| 2009 | 880 | Metric tons | 16.87% |
| 2010 | 1216 | Metric tons | 38.18% |
