Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 1497 | Metric tons | NA |
| 2005 | 4107 | Metric tons | 174.35 % |
| 2006 | 4395 | Metric tons | 7.01 % |
| 2007 | 4500 | Metric tons | 2.39 % |
