<?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:creator>Leonard Shapiro</dc:creator>
  <dc:date>1975</dc:date>
  <dc:description>&lt;p&gt;The rapid methods previously used by the U.S. Geological Survey to determine the major constituents of rocks have been modified to introduce atomic absorption spectrometry (AAS) where applicable. Two procedures are available for determining 10 constituents: one, from a single solution prepared by a nitric-acid dissolution of a lithium metaborate-lithium tetraborate fusion, and the other, a two-solution method in which one portion of sample is dissolved in an HF-H&lt;sub&gt;2&lt;/sub&gt;SO&lt;sub&gt;4&lt;/sub&gt;,-HNO&lt;sub&gt;3&lt;/sub&gt; mixture and another portion is fused with NaOH. In both techniques, SiO&lt;sub&gt;2&lt;/sub&gt;, Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;, Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;, TiO&lt;sub&gt;2&lt;/sub&gt;, P&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;5&lt;/sub&gt;, and MnO are determined spectrophotometrically, and CaO, MgO, Na&lt;sub&gt;2&lt;/sub&gt;O, and K&lt;sub&gt;2&lt;/sub&gt;O are determined by AAS. Separate portions of samples are used for the following determinations: FeO by titration with K&lt;sub&gt;2&lt;/sub&gt;Cr&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;7&lt;/sub&gt; after decomposition with HF and H&lt;sub&gt;2&lt;/sub&gt;SO&lt;sub&gt;4&lt;/sub&gt;; total H&lt;sub&gt;2&lt;/sub&gt;O by its weight when evolved on heating a mixture of sample plus flux; H&lt;sub&gt;2&lt;/sub&gt;O by loss of weight at 110° overnight; CO&lt;sub&gt;2&lt;/sub&gt; by its volume upon evolution with acid; fluorine by a new indirect measurement of SiO&lt;sub&gt;2&lt;/sub&gt; evolved with fluorine on heating; and. sulfur by a new procedure based on a turbidimetric measurement of BaSO&lt;sub&gt;4&lt;/sub&gt;, after an aqua regia attack. Several mechanical aids and automated devices are used for the analyses. &lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.3133/b1401</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>U.S. Government Printing Office</dc:publisher>
  <dc:title>Rapid analysis of silicate, carbonate, and phosphate rocks: Revised edition</dc:title>
  <dc:type>reports</dc:type>
</oai_dc:dc>