Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2005 | 700 | Thousand metric tons | NA |
| 2006 | 800 | Thousand metric tons | 14.29% |
| 2007 | 1300 | Thousand metric tons | 62.50% |
| 2008 | 900 | Thousand metric tons | -30.77% |
| 2009 | 1000 | Thousand metric tons | 11.11% |
| 2010 | 1000 | Thousand metric tons | 0.00% |
| 2011 | 1000 | Thousand metric tons | 0.00% |
| 2012 | 1100 | Thousand metric tons | 10.00% |
| 2013 | 1100 | Thousand metric tons | 0.00% |
