Rasamanjari 3.3

3.3

ete uparasāḥ proktāḥ śodhyā drāvyāśca mārayet /
<gandhaka>
tatrādau gandhakotpattiṃ śodhanaṃ tvatha kathyate //

these are declared to be the secondary minerals; they are to be purified, liquefied, and calcined.
<Sulphur>
Therein, first the origin of sulphur and then its purification is spoken of.