Anandakanda 1.4.316

1.4.316

tīkṣṇāṃśā tāravimalā sarvaṃ mūṣāgataṃ dhamet /
tatastaccūrṇayedamlaiḥ piṣṭvā ruddhvā puṭetpacet //

silver pyrites equal to the part of iron; one should smelt it all inside a crucible. / Then one should powder it, grind it with sours, seal it, and bake it in a calcination fire.