Strengthening mercury

To strengthen (brimhana) the mercury it is always made fire-resistant by tapana, vasana and kasana: rock salt, orpiment, Multani earth and grain husk are ground thick with juices, raisins and mushakani are added (as the commentary reads the verse), and the mercury, coated inside and out with mica paste, is covered and heated at the mouth of the fire with a dry fire of husk, cow-dung cakes and several kinds of charcoal. Then sarana is done with the prescribed oil and an equal part of liquid gold, a globule is made, given fourfold sarana and digested; siddha mercury so treated, given fourfold sarana again with grinding and cooking, becomes pratisarita, and that, given fourfold sarana into siddha mercury and digested, becomes the still better anusarita.