Reconstructing Indian alchemy: Making coral

Dagmar Wujastyk

New series!

Reconstructing Indian alchemy: Making coral

Our new series is based on recipes from the Nectar Mine Light on Mercury, the Rasaprakāśasudhākara, a Sanskrit alchemical text that probably dates to the sixteenth century. This work is a relatively late addition to the Indian alchemical, or rasashastra (= rasaśāstraṃ, रसशास्त्रं) corpus. It has some of the typical features of the later rasashastra works, such as its focus on the medicinal applications of mercurials rather than on their use in the pursuit of immortality or transcendent states. The work also provides a brief sketch of all eighteen mercurial procedures, following the sequence, if not the details, of the 10th-century Heart of Mercury (Rasahṛdayatantra).

However, the Nectar Mine Light on Mercury also features a chapter on making alchemical gold and silver, pearls and corals, and here, we see an even sharper departure from the early alchemical works than in its focus on medicine. Only some of the chapter’s recipes feature mercury. And even those that include mercury or cinnabar do not situate their products within the process of the gradual purification and potentiating of mercury. And finally, it seems that the intended use of the products is entirely mundane: several of the recipes note that the product will be suitable for sale on the market, though it is unclear in what way they are suitable and how they will be used.


The recipe (Rasaprakāśasudhākara, chapter 11, verses 138 – 140) reads:


शुद्धशङ्खस्य चूर्णं हि सूक्ष्मं कृत्वा प्रयत्नतः

अर्धभागं च दरदं चूर्णयेन्मतिमांस्ततः

सद्यः सूताविकक्षीरं तेन दुग्धेन मर्दयेत्

वर्तिं विधाय मतिमान्कार्पासास्थिषु स्वेदयेत्

स्वांगशीतं समुत्तार्य प्रवालं रुचिरं भवेत्

Having carefully ground purified conch shell into a fine powder,

an intelligent person should then grind half the amount of cinnabar,

and quickly triturate it with the milk of a cow that has just calved.

Having formed a bead, the intelligent person should steam it in a cotton seed (decoction).

After it has cooled down by itself and has been collected, it will be a bright coral.


Sounds quite simple, doesn’t it? Grind conch shell; add cinnabar powder; then milk; make a paste; form a bead; steam it with cotton seed: Voilà, coral!

Except. The conch should be purified, or cleansed, at least. The text reads "the powder of purified conch shell" - “śuddhaśaṅkhasya cūrṇaṃ”. “Purified” (śuddha) is a technical term in alchemical literature. What purification entails differs from substance to substance. You can usually find out what procedure to apply in the alchemical works’ sections on the materials used for their various operations: Many alchemical works feature information on the characteristics of various materials, and on how to make them fit for use. The Rasaprakāśasudhākara also has several sections on substances. However, none of them feature conch shell. Andrew suggests a simple procedure for purifying conch shell that he learned during his rasashastra training. It consists of boiling the conch in vinegar. He notes that this will help in breaking down the shell and that it will facilitate grinding. So for once, we go ahead without a textual reference.



Afterwards, I find a recipe in the Śārṅgadharasaṃhitā (2.11.70-72), a ca fourteenth- century ayurvedic work that recommends soaking conch shell in citron juice in the sun until the juice is dried up. Not exactly the same, but a similar principle of applying an acid.


Once Andrew has finished boiling the conch in vinegar for three hours, the hard labour of grinding begins. This takes one and a half hours, but Andrew said that he should probably have ground it for longer, to make the powder finer.


conch ground


Now for the cinnabar. Andrew has some natural cinnabar. The recipe does not call for purified cinnabar, but Andrew feels uncomfortable just using the raw material: In modern pharmacological rasashastra, one always applies purification procedures to all materials, since they are afterwards consumed. In our recipe, there is no indication that the artificial coral is destined for medical use or consumption. Natural coral is actually a medicinal ingredient in both Ayurveda and in the iatrochemical formulations of rasashastra. Indeed, the Rasaprakāśasudhākara describes the medicinal applications of coral in its seventh chapter (verse 13), which range from treatments against dyspnoea and cough to mental disorders caused by spirits and eye diseases. Coral is also indicated as an antitoxin. However, medical applications do not seem to apply for the products of chapter eleven. Still, Andrew also notes that applying some form of purification may again help with breaking down the cinnabar for powdering it, so we consult the Rasaprakāśasudhākara for a purification technique and find two different methods. One is in chapter eleven (verse 9), where it is part of a different recipe (for converting silver into gold) that uses cinnabar.


दरदं रोमदेशीयं गोमूत्रेणैव स्वेदयेत् /

दोलायन्त्रे चतुर्यामं पश्चाच्छुद्धतमो भवेत् //

One should steam cinnabar from Western countries with cow urine

in a swing-device for twelve hours. Afterwards, it will be most pure.


Well, I am not totally sure about the “Western countries”, which is my rendering of “romadeśīyaṃ”. In a sixteenth-century work, this is unlikely refer to the Roman empire, so I interpret it as referring to a foreign land, located to the West of India. Cinnabar is not native to the Indian subcontinent and would have had to be imported. In the sixteenth century, there were a number of cinnabar mines in European countries, with the most prolific one in Spain. The Spanish mine in Almadén was exploited from Roman times and was the most important cinnabar deposit in the world. However, the designation “roma” probably points to somewhat closer countries, perhaps Afghanistan, which had some cinnabar deposits. Notably, none of the other alchemical treatises refer to a “romadeśa”.


In any case, Andrew was familiar with this particular method of purifying cinnabar. However, the Rasaprakāśasudhākara (chapter 6, verse 80) also describes this method of purifying cinnabar:


कुष्माण्डखण्डमध्ये तु स्वेदितो लुकुचाम्बुना /

सकृत्संजायते शुद्धः सर्वकार्येषु योजयेत् //

Having been steamed with monkey fruit water inside a wax gourd,

it immediately becomes pure. One may apply it in all procedures.


Andrew had not heard of this procedure before and thought he would like to give it a try… and also apply the other, more standard procedure for good measure. It would be fair to say that this slowed us down considerably, mostly because it is not so easy to source monkey fruit (lakucā) and wax gourd (kuṣmāṇḍa) in Dorset in midwinter. By contrast, cow urine was sourced relatively easily from a neighbouring farmer. For the steaming or boiling in cow urine, you place the cinnabar pieces into a cloth, forming a bolus, which is then hung into a pot with boiling urine for… well, to be honest, just three hours, not twelve.

Here are some images of the other method, which involves making a monkey fruit decoction (apparently quite smelly); hollowing out the gourd and placing the cinnabar pieces into the hollow; enclosing the gourd, enveloping it in cloth; and hanging it into the boiling monkey fruit decoction. The recipe doesn’t specify for how long, so Andrew went with three hours.

Kushmanda with cinnabar pieces before cookingenveloped in clothdolayantraafter boilingKushmanda cinnabar boiled




So, after all that – possibly quite unnecessary – work, the cinnabar is ground into a fine powder. That took about two hours, and again, Andrew felt that perhaps he should have given it some more time. In any case, he then mixed the conch shell and cinnabar powders together. One question that arose in that context was whether “half the amount” referred to weight or volume. If weight, then we would have had to use quite large amounts of conch, since it was supposed to be double the amount of cinnabar: Cinnabar is much heavier than conch. So we went with volume.


crushed cinnabar


Now the milk. It was supposed to be the milk of a cow that had recently calved. Wrong time of the year for that and so Andrew just used fresh milk from Jersey cows (again, from the neighbouring farmer).



Mixing the cinnabar, conch shell, and milk took about one and a half hours. The mixture became quite gum-like near the end. Now it was time to form beads and steam them. And this is where we felt a little unsure of ourselves again. Usually, steaming involves some kind of container or pouch – often made from herbal ingredients to contain the material that needs to be purified (see, for example, the steaming of mercury in a herbal pouch and fig leaves in our first series of experiments). The pouch is then hung into or over a boiling liquid, often sour gruel. In our recipe, only cotton seed is mentioned for the steaming. We interpreted this as meaning that a decoction of cotton seed should be used as the steaming liquid, though perhaps the cotton seed was meant to be used to form a pouch for the cinnabar-conch-paste, with the steaming liquid left unspecified. We opted for the cotton seed decoction and this meant another wait, as Andrew had to order this in by mail. Mail orders can take a while during a pandemic, as we discovered. And cotton seed is expensive in the UK, as it is sold as a crop seed.

We still had the problem of how we were going to steam the cinnabar-conch paste. Just envelop it in cloth? Time to consult other alchemical works again! We found two recipes for making artificial coral in the Rasaratnākara (The Jewel Mine of Mercury, ca 13th-15th century). Both described the use of bamboo stalks for steaming a cinnabar-conch mixture. Here is the simpler recipe of the two (Rasaratnākara, Vādakhaṇḍa 19. 38-40):


दग्धः शङ्खः ससिन्दूरं समांशं चूर्णयेत्ततः /

क्षीरैः सद्यः प्रसूताया एडाया मर्दयेद्दृढं //

पूरयेच्च तृणोत्थे वा नाले वंशादिसंभवे /

सुपक्वे चान्नभाण्डे तु यवागूवर्जिते क्षिपेत् /

आच्छाद्य पच्यान्मन्दाग्नौ घटिकान्ते समुद्धरेत् //

प्रवाला नलिकागर्भे जायन्ते पद्मरागवत् //

One should powder incinerated conch with an equal amount of cinnabar and grind it firmly with the milk of a ewe that has recently delivered.

One should then fill it into a blade of straw or into a hollow bamboo stalk, etc.

And one should place it into a well-fired pot without sour gruel.

Having covered it, one should roast it on a slow fire and then retrieve it from the pot.

Inside the bamboo hollow, corals of a lotus-like colour are produced.


We thought we would go with the bamboo as the container for the beads: Andrew went ahead with that. But there was another issue: Both recipes from the Rasaratnākara specify that the conch is incinerated (dagdha). This gave us pause, because making an ash out of a substance is sometimes considered part of its purification process. Was our śuddhaśaṅkham – purified conch – meant to be conch ash?


As Andrew put it: “Omg, nightmare.” [Email, Mar 8, 2021]


He rallied quickly, however, and we decided to go forward with the paste he had already made and the bamboo stalks and cotton seed decoction.

We also did one bead just enveloped in cloth.



bamboo in cotton seed


After three hours of steaming, the result was this:


The pieces were a little brittle at first, but hardened as they dried. Andrew polished them, and applied some oil to stop them from cracking. I asked him to saw a piece in half: the piece was a bit too crumbly, though perhaps, if we had waited a few days it would have worked better. Andrew was able to drill holes in the beads after a few days. We also soaked the pieces in water to see whether they would start to dissolve. Gratifyingly, they didn’t.


soaking coralcoral with drill holescoral bead on string


So, this was more or less successful. Some quibbles included that the texture was a bit rough and one could see bits of mercury shining on the surface. The colour also wasn’t quite right: a bit more on the terracotta than on the red coral side, though it seemed to become redder after a while. Here Andrew suggested we might get better results by using artificial cinnabar or vermilion instead of natural cinnabar.

Since we were not entirely satisfied, we decided to redo the experiment, this time using conch ash and artificial cinnabar. I'll describe that in the next blog. Spoiler alert: the results were much better!





[All images ©Andrew Mason, neterapublishing]

Kushmanda with cinnabar pieces before cooking
Kushmanda with cinnabar pieces before cooking (one half)
enveloped in cloth
after boiling
Kushmanda cinnabar boiled
cinnabar pieces untreated
crushed cinnabar
bamboo in cotton seed
soaking coral
coral with drill holes
coral bead on string
conch ground
Reconstructing Indian alchemy: Making coral

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