Ancient alchemical texts exhibit a strong fascination with mercury due to its mechanochemical properties, which captivated early practitioners. The AlchemEast project conducted a thorough investigation into the specific procedures followed by ancient alchemists to extract mercury from cinnabar. Based on the treatment of this mineral—either through grinding or heating—we can classify these procedures into two distinct groups: “cold extraction” and “hot extraction”. The following section delves into the primary sources for the “cold extraction” methods.
The earliest known procedure for extracting mercury—that is, the earliest witness to a mechanochemical reaction—was recorded by the natural philosopher Theophrastus in his work On Stones (4th century BCE).
Mercury is produced by grinding cinnabar with vinegar in a copper mortar with a copper pestle. [see the replication]
ποιεῖται (scil. χυτὸν ἄργυρον) δὲ ὃταν <κιννάβαρι> τριφῇ μετ’ ὂξους ἐν ἀγγείῳ χαλκῷ καὶ δοίδυκι χαλκῷ.
A few centuries later, interesting variations were recorded in the work of the Graeco-Egyptian alchemist Zosimus of Panopolis. His writings include recipes that instruct on how to use lead mortars and pestles to grind cinnabar in water or vinegar or in the juice of an unidentified plant.
(Another) recipe: take a lead mortar and put cinnabar in it; then, grind it in water with a pestle comprised of lead, until quicksilver is produced. (Another) recipe: add vinegar and grind (cinnabar) in the sun. [see the replication]
ܣܝܪ. ܣܒ ܡܕܟܬܐ ܘܕܩܘܩܐ ܕܟܘܢ ܘܐܪܡܐ ܒܗ̇ ܩܝܢܒܪܝܣ ܘܫܚܘܩ ܒܡܝ̈ܐ ܥܕܡܐ ܕܗܘ̇ܐ ܗܕܘܪܘܪ ܓܘܪܘܢ. ܣܝܪ. ܐܚܪ̈ܢܐ ܕܝܢ ܚܠܐ ܪܡܝܢ ܘܫܚܩܝܢ ܒܫܡܫܐ
In another passage, Zosimus traces back the use of this equipment to first- to second-century authoritative sources. He claims that Maria the Jewess and Chymes used to grind cinnabar with pestles and mortars made of various metals, namely lead and tin.
I think that it is better to grind cinnabar […]. In fact, different substances produce quicksilver (lit. cloud) when they are processed with water or vinegar in the sun. And we know this from experience. And every book as well as Chymes and Maria say: “Lead mortar and lead pestle. Grind cinnabar with vinegar in the sun until quicksilver (lit. cloud) is produced”. They do the same with tin (mortars and pestles). [see the replication]
ἔγωγε νομίζω βέλτιον εἶναι κιννάβαριν συλλειοῦν […]. Καὶ γὰρ οἰκονομούμενα ἐν τῷ ἡλίῳ τὰ εἴδη ὕδατι ἢ ὄξει νεφέλην ἀποτίκτουσιν· καὶ τοῦτο διὰ πείρας ἐπιστάμεθα. Καὶ πᾶσαι αἱ γραφαὶ καὶ Χίμης καὶ ἡ Μαρία φησίν· θυΐα μολιβδίνη καὶ δoίδυξ μολίβδινος· κιννάβαριν ὄξει λείου ἐν ἡλίῳ ἕως γένηται νεφέλη. Ὁμοίως καὶ ἐπὶ κασσιτέρου πάλιν τὸ αὐτό.
These sources conveyed the idea that metals constituted a key ingredient in the procedure. Indeed, in a recipe only preserved in Syriac translation, Zosimus prescribes the grinding of cinnabar with copper scrapings and vinegar until droplets of mercury become visible.
Another (recipe). Take copper scrapings and grind (cinnabar) with water. Little by little you will collect the mercury (lit. cloud) that floats on the surface with a sponge, until all (the ingredients) have been exhausted and consumed. Then put (what is left) in a vessel without a lid; you will cover it with another vessel and place this vessel on a fire of sawdust. You will find mercury in the upper (vessel). [see the replication]
ܣܝܪ. ܣܒ ܫܘܦܐ ܕܒܠܬ<ܝ>. ܘܫܚܘܩ ܒܡܝ̈ܐ. ܒܐܝܕܐ ܒܐܝܕܐ ܗܘܝܬ ܫ̇ܩܠ ܥܢܢܐ. ܗܝ ܕܛܝܦܐ ܡܢ ܠܥܠ ܒܐܣܦܘܓܐ ܥܕܡܐ ܕܟܠܗ ܡܬܛܠܩ ܘܝܒܫ. ܘܐܪܡܝܗܝ ܒܙܒܘܪܐ ܕܠܝܬ ܠܗ ܟܣܝܐ. ܘܟܣܝܗ̇ ܒܐܚܪܬܐ. ܘܣܝܡ ܥܠ ܢܘܪܐ ܕܢܣܪܬܐ. ܘܡܫܟܚ ܐܢܬ ܠܥܠ ܐܝܟ ܥܢܢܐ
Here, two points deserve special attention: 1) the metal is added to the procedure as an independent reagent, and 2) the second part of the procedure is performed in a closed vessel (see section on Hot Extraction of Mercury: Sources).