Carbonatite and alkaline intrusive complexes, as well as their weathering products, are the primary sources of rare earth elements. A wide variety of other commodities have been exploited from carbonatites and alkaline igneous rocks including

Ground- and surface-water samples were collected in order to characterize the local ground-water flow system, determine metal concentrations in local ground water, and understand factors controlling the discharge of metal-rich waters from the mine.

This report examines potential sources of lanthanide elements [rare earth elements (REE)] with the objective of providing up-to-date geologic information regarding mineral commodities likely to have increased demand in the near term.

Periodic sampling of water during the spring of 2010 was carried out to understand the range and timing of variation in pH and metal concentration, and help evaluate variation in water quality during spring runoff.

Explains how and where rare-earth resources form and concentrate and how they are used and interact with the environment to affect human and ecosystem health. Discusses supply and demand trends and where undiscovered sources of rare-earths might be found.

Because of their unusual physical and chemical properties, the REEs have diverse defense, energy, industrial, and military technology applications including glass, petroleum refining, automobiles, and magnets.

Summarizes importance of rare earth elements, characteristics of REE deposits, REE-bearing minerals, and the types of mineral deposits that contain these elements.

Sedimentary deposits of dense minerals that accumulate with sand, silt, and clay in coastal environments, locally forming economic concentrations of the heavy miner­als.

Study focusing on the effects of historical mining on Forest Service lands in this area.