Gold is a medicine — if you know how to prepare it. That is the premise of the Rasamuktāvalī, a treatise on rasaśāstra, the branch of Ayurveda that works with metals and minerals. Its subject is hema bhasma, the calcined ash of gold, and the manuscript is a step-by-step recipe for making it: mercury, sulfur, a sealed crucible, and fire.
The furnace and the formula
The method is precise about equipment and proportions. Gold is ground with mercury and sulfur into a paste, formed into a ball, and fired in a covered dish inside a gaja-puṭa — the 'elephant-dung furnace.'
That auspicious ball placed in the middle of a covered dish, fired in a gaja-puṭa (elephant-dung furnace), is given with abundant fire. Mercury equal to gold, and purified sulfur of one-sixteenth part — this powder, ground with sour liquid, should be made into an auspicious ball. One should fire the gaja-puṭa daily with thirty forest stones, carefully processing mercury and sulfur. With fourteen auspicious firings, the delightful gold ash is easily obtained.
The numbers matter — equal mercury, a sixteenth part of sulfur, fourteen firings — because the whole enterprise is chemistry conducted in the language of ritual.
What gold ash was for
Once the gold has been reduced to ash, the text lists what it treats, and the list is long.
Purified gold (Hataka) bestows divine radiance, destroys wounds, asthma, cough, consumption, bile disorders, and wind disorders. It cures diabetes (prameha), disorders of the digestive tract (grahani), dysentery, skin diseases (kushtha), fever, and also cures impotence while kindling the fire of desire.
The same page adds that gold is bitter, astringent, and sweet, preserves youth, purifies speech, and removes wrinkles. This is a therapeutic tradition that treated the noble metals as medicines — and the preparation was everything.
A whole pharmacopoeia of metals
The Rasamuktāvalī does not stop at gold. Later sections walk through silver, copper, iron, tin, lead, and the secondary metals, each with its own purification, incineration, and list of indications — and each with the warning that improperly processed metal is worse than none at all. Reading it, you see a tradition that took mineral medicine seriously enough to write exact, repeatable procedures — a medieval laboratory manual in verse.
That which Prajapati covered — knowing this, the wise man should call it sahaja (innate). ||4|| That which fire itself created, being unbearable, born of the energy of Shiva — that fire-born (vahni-ja) pure gold is of three kinds, endowed with the luster of sixteen parts.
||4|| That which fire itself created, being unbearable, born of the energy of Shiva — that fire-born (vahni-ja) pure gold is of three kinds, endowed with the luster of sixteen parts. ||5|| That which is born in mountains from mines is said to be endowed with fourteen qualities.
||5|| That which is born in mountains from mines is said to be endowed with fourteen qualities. That which is produced from mercury and other rasas (minerals) is called vedhaja (transmutation-born), and it is the best for physicians.
Even with seven firings, the gold ash is thus produced in a purified state. ||14|| Now yet another method.
||14|| Now yet another method. || Pure mercury combined with sulfur, ground firmly with sour rice-water (kāñjika), making a very fine kājjalī (black sulfide paste), one should coat thin sheets of gold.
|| Pure mercury combined with sulfur, ground firmly with sour rice-water (kāñjika), making a very fine kājjalī (black sulfide paste), one should coat thin sheets of gold. ||15|| A pair of gentle crucibles (mūṣā) made from the bark of the kāñcanāra tree should be prepared.
Salutations to Sri Ganesha. Having first bowed to the younger brother of Girija (Ganesha) and to the lord of Girija (Shiva), and also to Brahma with devotion, I compose this delightful Rasa-Muktavali (a garland of pearls of rasa-shastra) for the benefit of others, dedicated to Kamalesh (Vishnu). ||1|| Now the measure/standard of metals is written. The wise declare the group of metals as: gold, silver, copper, iron (tikshna), tin (trapu), lead (bhujanga/naga), and zinc (maraka) — thus they speak, according to all the scriptures, though in great detail. ||2|| Now the classification of gold is written.
Having first bowed to the younger brother of Girija (Ganesha) and to the lord of Girija (Shiva), and also to Brahma with devotion, I compose this delightful Rasa-Muktavali (a garland of pearls of rasa-shastra) for the benefit of others, dedicated to Kamalesh (Vishnu). ||1|| Now the measure/standard of metals is written. The wise declare the group of metals as: gold, silver, copper, iron (tikshna), tin (trapu), lead (bhujanga/naga), and zinc (maraka) — thus they speak, according to all the scriptures, though in great detail. ||2|| Now the classification of gold is written. Gold is said to be of five kinds, out of respect, for the purpose of instructing beginners: natural (prakrita), innate/self-born (sahaja), fire-born (vahni-sambhava), mine-born (svakara-udbhava), and mercury-transmuted (rasendra-vedhaja).
||1|| Now the measure/standard of metals is written. The wise declare the group of metals as: gold, silver, copper, iron (tikshna), tin (trapu), lead (bhujanga/naga), and zinc (maraka) — thus they speak, according to all the scriptures, though in great detail. ||2|| Now the classification of gold is written. Gold is said to be of five kinds, out of respect, for the purpose of instructing beginners: natural (prakrita), innate/self-born (sahaja), fire-born (vahni-sambhava), mine-born (svakara-udbhava), and mercury-transmuted (rasendra-vedhaja). ||3|| That which arose from the rajoguna at the time of the creation of the world is called prakrita (natural) gold.
||12|| In a covered dish firing, a ball of sulfur equal in size to the ball should be placed around it. Then afterward, the upper part of the covered vessel should be sealed and fired in its own fire of cow-dung heaps.
Then afterward, the upper part of the covered vessel should be sealed and fired in its own fire of cow-dung heaps. ||13|| Thirty well-dried, firm forest stones should be given continuously in each and every firing.