Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 12097 | Kilograms | NA |
| 2003 | 11119 | Kilograms | -8.08 % |
| 2004 | 19240 | Kilograms | 73.04 % |
| 2005 | 24120 | Kilograms | 25.36 % |
| 2006 | 22561 | Kilograms | -6.46 % |
| 2007 | 17473 | Kilograms | -22.55 % |
| 2008 | 15184 | Kilograms | -13.10 % |
| 2009 | 9803 | Kilograms | -35.44 % |
