Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 2400 | Metric tons | NA |
| 2004 | 2300 | Metric tons | -4.17% |
| 2005 | 2300 | Metric tons | 0.00% |
| 2006 | 2300 | Metric tons | 0.00% |
| 2007 | 2000 | Metric tons | -13.04% |
| 2008 | 2000 | Metric tons | 0.00% |
| 2009 | 4562 | Metric tons | 128.10% |
| 2010 | 6270 | Metric tons | 37.44% |
| 2011 | 7789 | Metric tons | 24.23% |
| 2012 | 6992 | Metric tons | -10.23% |
| 2013 | 1500 | Metric tons | -78.55% |
