Anandakanda 2.2.15

2.2.15

<svarṇaśuddhi>
valmīkamṛttikā dhūmaṃ gairikaṃ ceṣṭakā paṭu /
ityete mṛttikāḥ pañca jambīrair vāranālakaiḥ //

Purification of gold:
Termite mound soil, soot, red ochre, brick, and salt:
having ground these five soils with jambīra lime juices or sour gruel,