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<article article-type="research-article">
<front>
<journal-meta>
<journal-id journal-id-type="archive">gsminmag</journal-id>
<journal-title>Mineralogical Magazine</journal-title>
<abbrev-journal-title abbrev-type="full">Mineralogical Magazine</abbrev-journal-title>
<issn pub-type="ppub">0026-461X</issn>
<publisher>
<publisher-name>Mineralogical Society</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.1180/minmag.1983.047.342.07</article-id>
<title-group>
<article-title>Fluocerite and Its Alteration Products from the Afu Hills, Nigeria</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname>Styles</surname>
<given-names>M. T.</given-names>
</name></contrib>
<contrib contrib-type="author">
<name>
<surname>Young</surname>
<given-names>B. R.</given-names>
</name></contrib>
<aff>Institute of Geological Sciences, Exhibition Road, London SW7 2DE</aff></contrib-group>
<pub-date pub-type="ppub">
<month>3</month>
<year>1983</year>
</pub-date>
<volume>47</volume>
<issue>342</issue>
<fpage>41</fpage>
<lpage>46</lpage>
<history>
<date date-type="received">
<day>25</day>
<month>2</month>
<year>1982</year>
</date>
<date date-type="rev-recd">
<day>8</day>
<month>6</month>
<year>1982</year>
</date></history>
<copyright-statement>Copyright &#x00A9; 1983, The Mineralogical Society</copyright-statement>
<copyright-year>1983</copyright-year>
<abstract>
<title>Abstract</title>
<p>Eluvial pebbles from the Afu Hills, Nigeria, are largely composed of fluocerite, Ce<sub>0.50</sub>La<sub>0.28</sub>Nd<sub>0.11</sub> Pr<sub>0.04</sub>Th<sub>0.03</sub>Ca<sub>0.02</sub>F<sub>3</sub>, with minor monazite. The fluocerite shows two types of alteration, to bastn&#x00E4;site, and to bastn&#x00E4;site-(La) with cerianite. Electron microprobe analyses are given for fluocerite, monazite, bastn&#x00E4;site and bastn&#x00E4;site-(La). The refined cell parameters of the fluocerite are <italic>a</italic> = 7.130&#x00B1;0.001, <italic>c</italic> = 7.298<sub>5</sub> &#x00B1; 0.001 &#x00C5;. Strongest lines are 3.204 &#x00C5; (100), 3.65 (45), 2.059 (45), 2.010 (45) and 3.56<sub>5</sub> (40). Space group <italic>P</italic> 6<sub>3</sub>/<italic>mcm</italic>, Z = 6, <italic>D</italic><sub>calc.</sub> = 6.12 g cm<sup>&#x2212;3</sup>, <italic>&#x03C9;</italic> = 1.613, <italic>&#x03B5;</italic> = 1.609 both &#x00B1;0.002, uniaxial negative. For bastn&#x00E4;site <italic>a</italic> = 7.131 &#x00B1; 0.002, <italic>c</italic> = 9.786&#x00B1;0.004 &#x00C5;, for cerianite <italic>a</italic> = 5.46<sub>0</sub> &#x00B1; 0.005 &#x00C5;.</p></abstract>
</article-meta>
</front>
</article>
