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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent LEFT JOIN category ON category.patent = patent.patent AND category.type = patent.type WHERE (category.class = '501') AND (category.subclass = '143') ORDER BY date ASC, patent, type

Total of 3 patents found where: Class is '501'; Subclass is '143';

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T / S Patent Date Description Patentee Category Assigned To
 1914
U Specimen known 1,091,678 March 31, 1914 Insulating Composition
Boro-silicate glass		 LOCKE, Fred M.
 Boron  
 1915
U Specimen known 1,127,042 February 2, 1915 Manufacture of High Potential Porcelain and Glass Insulators
Boro-silicate glass		 LOCKE, Fred M.
 Boron  
 1929
U 1,723,174 August 6, 1929 Use of Dumortierite
Porcelain composition use the mineral dumortierite which allows firing at a lower temperature		 JEFFERY, Joseph A.
RIDDLE, Frank H.
 Porcelain Champion Porcelain Co.

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