Rasarnava 4.32

4.32

gārā dagdhā tuṣā dagdhā dagdhā valmīkamṛttikā
ajāśvānāṃ malaṃ dagdhaṃ yāvattat kṛṣṇatāṃ gatam //

Burnt clay plaster, burnt husks, burnt anthill earth,
and burnt dung of goats and horses, until it has turned black;