Anandakanda 1.9.15

1.9.15

andhritaṃ vajramūṣāyāṃ dhamedbhasmati pāradaḥ /
<caturthaḥ prakāraḥ>
ghanajīrṇaṃ rasaṃ gandhaṃ tryahaṃ tulyaṃ vimardayet //

Enclosed in a vajra-crucible, one should blow upon it; the mercury turns into ash.
<Fourth method>
One should grind mercury that has digested mica and equal sulphur for three days