Category:Tests on clay materials available in Illinois coal mines (1917)

Media in category "Tests on clay materials available in Illinois coal mines (1917)"

The following 4 files are in this category, out of 4 total.

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  Tests on clay materials available in Illinois coal mines (1917) (14593506350).jpg 1,932 × 3,508; 1.27 MB
  
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  Tests on clay materials available in Illinois coal mines (1917) (14757216246).jpg 2,562 × 4,107; 570 KB
  
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  Tests on clay materials available in Illinois coal mines (1917) (14757219376).jpg 4,096 × 2,562; 499 KB
  
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  Tests on clay materials available in Illinois coal mines (IA testsonclaymater18stul).pdf 839 × 1,291, 134 pages; 8.25 MB