<?xml version="1.0"?>
<!DOCTYPE article SYSTEM "journalpublishing.dtd">
<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.1976.040.313.02</article-id>
<title-group>
<article-title>Iraqite, a New Rare-Earth Mineral of the Ekanite Group</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname>Livingstone</surname>
<given-names>A.</given-names>
</name>
<aff>Department of Geology, the Royal Scottish Museum, Edinburgh, EH1 1JF</aff></contrib>
<contrib contrib-type="author">
<name>
<surname>Atkin</surname>
<given-names>D.</given-names>
</name></contrib>
<contrib contrib-type="author">
<name>
<surname>Hutchison</surname>
<given-names>D.</given-names>
</name>
<aff>Geochemical Division, Institute of Geological Sciences, 64/78 Gray's Inn Road, London WC1X 8NG</aff></contrib>
<contrib contrib-type="author">
<name>
<surname>Al-Hermezi</surname>
<given-names>H. M.</given-names>
</name>
<aff>Nuclear Research Institute, Tuwaitha, Baghdad, Iraq</aff></contrib></contrib-group>
<pub-date pub-type="ppub">
<month>3</month>
<year>1976</year>
</pub-date>
<volume>40</volume>
<issue>313</issue>
<fpage>441</fpage>
<lpage>445</lpage>
<history>
<date date-type="received">
<day>16</day>
<month>1</month>
<year>1975</year>
</date>
<date date-type="rev-recd">
<day>14</day>
<month>4</month>
<year>1975</year>
</date></history>
<copyright-statement>Copyright &#x00A9; 1976, The Mineralogical Society</copyright-statement>
<copyright-year>1976</copyright-year>
<abstract>
<title>Summary</title>
<p>Iraqite, a new mineral of the ekanite group from northern Iraq, has the composition (Ln<sub>1&#x00B7;33</sub> Th<sub>0&#x00B7;66</sub> <italic>x</italic><sub>0&#x00B7;15</sub>) (K<sub>1&#x00B7;07</sub> <italic>y</italic><sub>0&#x00B7;93</sub>) (Ca<sub>3&#x00B7;49</sub> Ln<sub>0&#x00B7;35</sub> Na<sub>0&#x00B7;16</sub>) (Si<sub>15&#x00B7;69</sub> Al<sub>0&#x00B7;27</sub>) (O<sub>39&#x00B7;93</sub> F<sub>0&#x00B7;07</sub>) where <italic>x</italic> = U, Pb, Zr, Fe, Mg, and Cu, and <italic>y</italic> is presumed to be vacant sites. It occurs in granite in contact with dolomitic marble. The colour is pale greenish yellow; H 4&#x00BD; <italic>D</italic><sub>calc</sub> 3&#x00B7;28 and <italic>D</italic><sub>meas</sub> 3&#x00B7;27 (Berman balance), both corrected for minor impurity and non-structural water. Optically it is uniaxially negative with <italic>&#x03C9;</italic> 1&#x00B7;590 and &#x03B5; 1&#x00B7;585 though some sections show anomalous extinction up to 7&#x00B0;. Space group is <italic>P</italic>4/<italic>mcc</italic> with <italic>a</italic> 7&#x00B7;61&#x00B1;0&#x00B7;01 and <italic>c</italic> 14&#x00B7;72&#x00B1;0&#x00B7;02 &#x00C5;. Strongest lines of the indexed powder pattern are 5&#x00B7;28(100), 3&#x00B7;31(100), 2&#x00B7;64(100), 7&#x00B7;36(80), 3&#x00B7;38(80), 3&#x00B7;40(60), 2&#x00B7;7(40), 7&#x00B7;62(30). Thermal data are given.</p></abstract>
</article-meta>
</front>
</article>
