kasauti | कसौटी
A kasauti (Devanagari: कसौटी ISO15919: kasauṭī) stone, also known as a touchstone, is a fine-grained dark stone, often used in testing purity of gold. A simple test involves rubbing the gold object on the stone, leaving a streak. By comparing the streak's color to that of a sample with a known gold content, one can assess the purity of the gold.
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