Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 17000 | Kilograms | NA |
| 2003 | 22476 | Kilograms | 32.21% |
| 2004 | 22000 | Kilograms | -2.12% |
| 2005 | 16700 | Kilograms | -24.09% |
| 2006 | 10721 | Kilograms | -35.80% |
| 2007 | 10559 | Kilograms | -1.51% |
| 2008 | 18132 | Kilograms | 71.72% |
| 2009 | 16950 | Kilograms | -6.52% |
| 2010 | 18300 | Kilograms | 7.96% |
| 2011 | 18648 | Kilograms | 1.90% |
| 2012 | 10333 | Kilograms | -44.59% |
