
Mercury: The King of Medicines
Rasaratnākara, attributed to Nityanātha, argues rasa — mercury — is superior to all other medicines, and sets out the purification and calcination that turn it into ash.

This Sanskrit manuscript, titled *Rasa Ratnākara* ("Jewel-Mine of Mercury") by Nityanātha Siddha, is a foundational text of Indian alchemical medicine (Rasaśāstra), preserved in the Rajasthan Prācyavidyā Pratiṣṭhāna collection. The opening verses establish the text's comprehensive scope across five sections (pañcakhaṇḍa)—addressing medical therapeutics, rejuvenation (rasāyana), tantric siddhi, and mercury purification—while invoking Śiva and Caṇḍikā as divine patrons of the alchemical arts. The sample reveals sophisticated technical discourse on *rasāriṣṭa* (mercury toxicity) and *śodhana* (purification), prescribing ritual mantras, herbal adjuncts, and specialized apparatus such as the ūrdhvapātana-yantra for sublimation. Notably, the text synthesizes earlier authorities including Nāgārjuna, Caraka, and Suśruta, positioning itself as a curated compendium (*sārabhūta*) of practical knowledge validated through direct experience (*svānubhūta*) rather than textual transmission alone.