यद्घनानां तीक्ष्णेनोल्लिखन्ति तदुल्लेखनम् ॥ कZ_०२.१४.४७ ॥
yad ghanānāṃ tīkṣṇenollikhanti tad ullekhanam
When they scrape solid articles with a sharp tool to remove material, that is scraping (ullekhana).
Scraping can be hidden as routine finishing/engraving while steadily reducing weight or thickness without obvious breakage.