<?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>L. Paul Greenland</dc:contributor>
  <dc:creator>E.G. Lillie</dc:creator>
  <dc:date>1973</dc:date>
  <dc:description>&lt;p&gt;Samples are decomposed with hydrofluoric acid and&amp;nbsp;perchloric acid in the presence of W&lt;sup&gt;181&lt;/sup&gt; tracer. Molybdenum is&amp;nbsp;extracted from a hydrochloric acid solution with tributyl phosphate.&amp;nbsp;Tungsten is separated from most other elements by extraction of the&amp;nbsp;a-benzoinoximate into chloroform. Stannous chloride in concentrated&amp;nbsp;hydrochloric acid is used to strip tungsten and reduce it to W&lt;sup&gt;+5&lt;/sup&gt; . The&amp;nbsp;amount of tungsten is determined spectrophotometrically after extraction&amp;nbsp;as the thiocyanate complex into amyl alcohol. The correction for&amp;nbsp;chemical losses is determined by counting W&lt;sup&gt;181&lt;/sup&gt;.&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:language>en</dc:language>
  <dc:publisher>U.S. Geological Survey</dc:publisher>
  <dc:title>Spectrophotometric determination of tungsten in rocks by an isotope dilution procedure</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>