Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 643 | Metric tons | NA |
| 2004 | 1448 | Metric tons | 125.19% |
| 2005 | 7900 | Metric tons | 445.58% |
| 2006 | 6600 | Metric tons | -16.46% |
| 2007 | 6300 | Metric tons | -4.55% |
| 2008 | 7067 | Metric tons | 12.17% |
| 2009 | 6987 | Metric tons | -1.13% |
| 2010 | 17833 | Metric tons | 155.23% |
| 2011 | 32146 | Metric tons | 80.26% |
| 2012 | 26500 | Metric tons | -17.56% |
