<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Shyama P. Sinha</dc:contributor>
  <dc:contributor>Valery D. Kosynkin</dc:contributor>
  <dc:creator>James B. Hedrick</dc:creator>
  <dc:date>1997</dc:date>
  <dc:description>The mineral loparite (Ce, NA, Sr, Ca)(Ti, Nb, Ta, Fe+3)O3 is the principal ore of the light-group rare-earth elements (LREE) in Russia. The complex oxide has a perovskite (ABO3) structure with coupled substitutions, polymorphism, defect chemistry and a tendency to become metamict. The A site generally contains weakly bonded, easily exchanged cations of the LREE, Na and Ca. The B site generally contains smaller, highly charged cations of Ti, Nb or Fe+3. Mine production is from Russia's Kola Peninsula. Ore is beneficiated to produce a 95% loparite concentrate containing 30% rare-earth oxides. Loparite concentrate is refined by either a chlorination process or acid decomposition process to recover rare-earths, titanium, niobium and tantalum. Rare-earths are separated by solvent extraction and selective precipitation/dissolution. The concentrate is processed at plants in Russia, Estonia and Kazakstan.</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1016/S0925-8388(96)02824-1</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Elsevier Science S.A.</dc:publisher>
  <dc:title>Loparite, a rare-earth ore (Ce, Na, Sr, Ca)(Ti, Nb, Ta, Fe+3)O3</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>