Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 4950 | Kilograms | NA |
| 2003 | 4269 | Kilograms | -13.76% |
| 2004 | 4500 | Kilograms | 5.41% |
| 2005 | 4400 | Kilograms | -2.22% |
| 2006 | 4300 | Kilograms | -2.27% |
| 2007 | 3401 | Kilograms | -20.91% |
| 2008 | 2721 | Kilograms | -19.99% |
| 2009 | 5400 | Kilograms | 98.46% |
| 2010 | 4215 | Kilograms | -21.94% |
| 2011 | 2372 | Kilograms | -43.72% |
| 2012 | 3000 | Kilograms | 26.48% |
