However, rare earth metals have been falling since. Other countries began developing their own supplies and many countries, including Brazil, India, the U.S. and South Africa, have all been major producers in the past. As prices increased, companies reopened facilities. Consequently, China’s market share has declined to about 86% and the country’s exports now frequently fall short of maximum levels under the quota system.

REMX includes a large China tilt at 26.2%, followed by U.S. 18.0%, Australia 11.9%, Japan 9.0% and France 7.0%.

Market Vectors Rare Earth/Strategic Metals ETF

For more information on the rare earths industry, visit our rare earth metals category.

Max Chen contributed to this article.