Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2005 | 7.07399988174438 | Metric tons | NA |
| 2006 | 49.7190017700195 | Metric tons | 602.84% |
| 2007 | 88.25 | Metric tons | 77.50% |
| 2008 | 99.9229965209961 | Metric tons | 13.23% |
| 2009 | 129.279998779297 | Metric tons | 29.38% |
| 2010 | 194.682998657227 | Metric tons | 50.59% |
| 2011 | 272.77099609375 | Metric tons | 40.11% |
| 2012 | 204.554992675781 | Metric tons | -25.01% |
