Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 2 | Metric tons | NA |
| 2003 | 2 | Metric tons | 0.00% |
| 2004 | 2 | Metric tons | 0.00% |
| 2005 | 2.99900007247925 | Metric tons | 49.95% |
| 2006 | 2.92899990081787 | Metric tons | -2.33% |
| 2007 | 3 | Metric tons | 2.42% |
| 2008 | 3.72000002861023 | Metric tons | 24.00% |
| 2009 | 4.49100017547607 | Metric tons | 20.73% |
| 2010 | 6.99499988555908 | Metric tons | 55.76% |
| 2011 | 7.92700004577637 | Metric tons | 13.32% |
| 2012 | 10.2069997787476 | Metric tons | 28.76% |
