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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 = '67') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '501'; Subclass is '67';

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T / S Patent Date Description Patentee Category Assigned To
 1933
U 1,923,221 August 22, 1933 Process of Melting Glass
Boro-silicate glass, method to make colorless by using graphite pot		 LOCKE, Fred M.
LOCKE, Fred J.
 Boron Corning Glass Works

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