A rare-earth mineral contains one or more rare-earth elements as major metal constituents. Rare-earth minerals are usually found in association with alkaline to peralkaline igneous magmas in pegmatites or with carbonatite intrusives. Perovskite mineral phases are common hosts to rare-earth elements within the alkaline complexes. Minerals are solids composed of various inorganic elements,^[1] mixed through processes such as evaporation, pressure or other physical changes.^{[2] [3]} Rare earth minerals are rare because rare earth elements have unique geochemical properties that prevent them from easily forming minerals,^[4] and are therefore not normally found in deposits large or concentrated enough for mining.^[4] This is the reason they are called "rare" earths. ^{[4] [5]} These elements have a wide range of uses from every day items to military technologies.^[6] The minerals that do exist are often associated with alkaline magmas or with carbonatite intrusives. Perovskite mineral phases are common hosts to rare-earth elements within the alkaline complexes. Mantle-derived carbonate melts are also carriers of rare earths. Hydrothermal deposits associated with alkaline magmatism contain a variety of rare-earth minerals.

The following list includes the more common hydrothermal minerals that often contain significant rare earth elements:

These minerals contain the 16 elements that are considered rare in our planet's crust.^{[7] [7]} The presence of these minerals can be a valuable indicator in geological surveys and mineral resource assessments.^{[8] [8]} There are over 160 rare earth minerals known, but only four of these occur in amounts suitable for mining.^[9] They can occur in either primary or secondary deposits.^[10]

Primary deposits result from hydrothermal and igneous processes while secondary deposits are sedimentary and formed through weathering processes.^[11] In the case of primary deposits, the minerals are generally found in the specific location where the elements came together to form the deposit.^{[12] [12]} Secondary deposits have undergone metamorphic or sedimentary processes in a location different from where the minerals were actually formed.^{[13] [14]} Depending on the type of deposit, various methods can be employed to extract the minerals from both primary and secondary deposits.^{[15] [15] [16]}

Bastnäsite is a rare, semi-soluble carbonate mineral, primarily mined for its yttrium, used to make ^[17] magnets for speakers, microphones, communication devices, and many other modern necessities.^{[18] [19] [19]} Bastnäsite deposits are found in China, Madagascar and the USA.^[19]

Laterite is a class of materials which contain significant amounts of aluminium and iron.^[22] They can form clays able to hold many minerals within them.^[22] The weathering of rocks by leaching and oxidising conditions results in the formation of clay-like ^[22] minerals such as goethite, lepidocrocite, and hematite.^[22] Some of them can hold rare earth minerals as well as iron, nickel and the alumina for which it is often mined.^{[23] [24] [24]} Laterite results from the weathering of basalt.^[23][24] It can make a stable basis for construction since it solidifies into rock when exposed to air.^[24] However, its low fertility makes it unsuitable for agricultural use.^[24]

Monazite is a waxy mineral that is formed through the crystallization of igneous rocks and the metamorphism of clastic sedimentary rocks.^[25] This mineral is typically mined in placer deposits, with gold commonly found as a byproduct.^{[25] [25]} Monazite contains many rare metals such as neodymium cerium, lanthanum, praseodymium, and samarium, making it a critical material for renewable energy devices.^[26][25] Monazite sand and deposits for mining are found in India, Brazil, and Australia.^[27]

Loparite is a mineral that is mined for the three rare (but not rare earth) elements: titanium, niobium, and tantalum it contains.^[28][28] Major Loparite deposits can be found in Russia and Paraguay,and although it is present in other countries such as Canada, Norway, Greenland, and Brazil,^[29] Russia remains the primary source for mining this mineral.^[29] The elements in loparite make it useful for conductivity, aircraft assembly, and as a radioactive tracer.^[28]

Kyawthuite is a rare mineral because the extreme pressure needed for its formation is very uncommon. ^[30] Unlike other minerals, it is created from a pegmatite deposit within an igneous rock.^[31] Its deep red-brown colour and high density come from the crystal assemblages within it.^[32] The mineral contains lead, thallium, and oxygen that have undergone oxidation, as well as the rare metals bismuth and antimony.^[31] Interestingly, the mineral is named after Dr. Kyaw Thu, a former geologist at the University of Yangon who discovered it.^[31] It is found in the region of Myanmar Mogok.^[33]

• Jones, Adrian P., Francis Wall and C. Terry Williams, eds. (1996) Rare Earth Minerals: Chemistry, Origin and Ore Deposits, The Mineralogy Society Series #7, 372 pp. ISBN 978-0-412-61030-1
• China New Policy Affect Rare Earth Price