Anandakanda 1.24.3

1.24.3

naṣṭapiṣṭaṃ ca śuṣkaṃ ca dhmātaṃ khoṭo bhavetpriye /
sauvīraṃ ṭaṅkaṇaṃ kācaṃ dattvā dattvā tu śodhayet //

ground until destroyed, dried, and blown, becomes a khoṭa lump, O dear one.
Having repeatedly added antimonite, borax, and glass, one should purify it.