Anandakanda 1.25.27

1.25.27

kṣipennirvāhaṇaṃ dravye nirvāhye samabhāgikam /
āvāpyaṃ vāpanīyaṃ ca bhāge dṛṣṭe ca dṛṣṭavat //

One should cast the discharging agent (nirvāhaṇa) in equal parts into the substance to be discharged (nirvāhya); / the additive (āvāpya) and the base metal (vāpanīya) should be treated in the proportion observed [by tradition].