{"thcode":2,"term":{"code":1553,"name":"rare earth elements","parent":1426,"scope":"A group of elements including the lanthanoids, or lanthanides, of interest because they are used in modern technological industries.  Yttrium and scandium are often included in this group."},"uf":[],"bt":[{"code":1426,"name":"chemical element groups","parent":1382,"scope":"Groups shown at <http:\/\/periodic.lanl.gov\/>"},{"code":1382,"name":"elements","parent":1174,"scope":"Chemical elements and element groups"},{"code":1174,"name":"topics","parent":1,"scope":"Themes, subjects, and concerns for which USGS information resources are relevant."},{"code":1,"name":"Categories","parent":null,"scope":"Thematic terms for categorizing information resources.  This thesaurus is intended to support finding and understanding scientific information."}],"nt":[],"rt":[{"code":1489,"name":"lanthanide series elements","parent":1426,"scope":null},{"code":1569,"name":"scandium","parent":1427,"scope":"Metal element with symbol Sc and atomic number 21 <http:\/\/periodic.lanl.gov\/21.shtml>"},{"code":1617,"name":"yttrium","parent":1427,"scope":"Metal element with symbol Y and atomic number 39 <http:\/\/periodic.lanl.gov\/39.shtml>"}]}