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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 = '423') AND (category.subclass = '422') ORDER BY type ASC, date, patent

Total of 1 patents found where: Class is '423'; Subclass is '422';

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T / S Patent Date Description Patentee Category Assigned To
 1919
U 1,312,053 August 5, 1919 Process of Decomposing Potassium Silicates
Process of extracting potassium to be used in glass manufacture (see patent 1,327,781; 1,327,782)
SCHOLES, Samuel R.
Glass H. C. Fry Glass Co.

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