Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
Year | Production | Unit of Measure | % Change |
2002 | 3500 | Metric tons | NA |
2003 | 3600 | Metric tons | 2.86 % |
2004 | 3700 | Metric tons | 2.78 % |
2005 | 3700 | Metric tons | 0.00 % |
2006 | 3900 | Metric tons | 5.41 % |
2007 | 3900 | Metric tons | 0.00 % |
2008 | 4000 | Metric tons | 2.56 % |
2009 | 8656 | Metric tons | 116.40 % |
2010 | 8773 | Metric tons | 1.35 % |
2011 | 13784 | Metric tons | 57.12 % |
2012 | 13700 | Metric tons | -0.61 % |
2013 | 14250 | Metric tons | 4.01 % |