Rasashastra, an integral part of Ayurveda, deals with the drugs of mineral origin, and details their varieties, characteristics, processing techniques, properties, therapeutic uses, possibilities of developing adverse effects and their management etc. in a comprehensive way.

Although the roots of this science (Rasa Shastra) exist in the ancient texts of Indian civilization, its development as an independent system of therapy started around the 8th century A.D. Ayurvedic classics written before that time, like Charaka Samhita and Sushruta Samhita etc. contain descriptions of metals and minerals, their processing techniques and their utilization in therapeutics etc.

In the perspective article I am trying to explain about the most common metals and mineral used in Ayurveda.

Though the western scientific community expresses concern about the safety of Ayurvedic Herbal, Herbo-mineral and metallic preparations, these formulations are widely used in Indian System of Medicine.

First let us look at the Metal Mercury in detail.

 Metal Description  Types of preparation Therapeutic Indications
Parada/Mercury Rasa is the synonym of Mercury used in Ayurveda. The

evolvement of Rasa Shastra as a specialized branch is traced to the great Buddhist Sage Naagaarjuna. Who

is considered as ‘Father of Rasa-Shastra’.

Naagaarjuna proclaimed

“Siddhe Rase Karishyaami Nirdaridryamidam jagat” – meaning that I am experimenting with the

mercury to eliminate poverty from this world.

It is believed that processed mercury (Bhasma) eliminates all sorrow of eldery age and

diseases of body and mind. The bonding of mercury with certain herbs and sulfur provides khechari – gati (able to fly). There is none material as kind in the universe as aforesaid

mercury is for human race!


Purification of Mercury – Mercury has been purified by carrying Ashta-Sanskar (eight steps of purification) or

has been extracted from Hingul (Cinnabar), but has not undergone six times processing

(absorption) with Sulphur, then, it will never be completely therapeutically potent. Therefore,

it is a must to do six times absorption of Sulphur into Mercury to make it therapeutically


Based on the method of preparation, the mercury-based drugs are classified as

1. Khalvi rasa – Mercury and sulphur and / or other herbal or mineral / metal ingredients are ground together in a mortar to produce a finely powdered drug. Since the mercury and other ingredients of the formulation are grinded in a mortar, known as ‘Khalva’ as per the terminology of Ayurved, the formulation is known and classified as ‘Khalvi Rasa’.


2. Parpati rasa – Mercury and sulphur are first ground, if prescribed, with specified metal bhasma, if not, without metal bhasma, to prepare a homogeneous black coloured fine powder termed as ‘Kajjali’. The powdered mass ‘Kajjali’ is then subjected to controlled heating in an iron spatula to obtain a molten mass. The molten mass is then immediately poured and spread evenly on a flat soft surface, preferably on the surface of a banana leaf, which is usually placed on a soft surfaced platform prepared from fresh wet cow dung or mud. The soft material like fresh cow dung or mud is selected for this procedure to provide smooth and even platform for the leaf placed on it and to facilitate free flow and even spread of the liquefied kajjali on the surface of the leaf. The poured mass is then immediately covered with another banana leaf and is hand pressed evenly. The covered leaf is then removed to find a thin flat sheet of the material, which is termed as ‘Parpati’.


3. Kupipakwa rasa – Mercurial drug preparations prepared by subjecting the ‘Kajjali’ (a product obtained by grinding mercury with sulphur and /or prescribed mineral and metal ingredients) to controlled heating in a narrow mouth high long neck glass flask termed as ‘Kupi’, or sometimes in an earthenware crucible termed as ‘Mushaa’ or in a metallic crucible; is termed as ‘Kupipakwa Rasa’.


4. Pottali rasa – The ‘Kajjali’, prepared with prescribed ingredients is wrapped tightly in a silk cloth to prepare a bundle termed as ‘Pottali’. Sulphur powder of required quantity is taken in a stainless steel or earthenware wide mouthed pan. The pan is kept on fire and the sulphur is allowed to melt. The molten sulphur serves the purpose of sulphur bath for the ‘pottali’. The above described bundle of ‘kajjali’ i.e. pottali is immersed in the sulphur bath, which is subjected to intensive heating. (Adequate temperature to keep the Sulphur in a molten sate for a reasonable period to achieve hardening of the mass being fried, is maintained.) The powder mass of ‘Kajjali’ bundled in silk cloth gets hardened by this intensive heating and gets converted into a hardened ball termed as ‘Pottali’ Rasa. The silk cloth wrapped around the ‘kajjali’ is burnt during the process and sticks to the hardened ball. This burnt cloth is removed by scratching the hardened ball, which then becomes ready for use.


The hard ball is rubbed on a stone slab moistened with water and the paste generated due to rubbing is collected and given to the patient for licking. The rubbing is performed in circular motion. The number of rounds of rubbing will be decided in accordance with the requirement of the prescribed dose of the drug. The ‘Pottali Rasa’ is said to be most instantly acting drug formulation among all and is usually prescribed in medical emergencies.



‘Rasavaidyaas’ use characteristics of Mercury, as a standard of pharmaceutical actions of mineral and metallic drug preparation. Particularly in case of metal ‘Bhasma’ it is said that the metals when converted into ‘Bhasma’ acquire the characteristics of Mercury and become capable of strengthening the body and curing the disease. In this respect a term ‘Rasibhavana’ meaning becoming ‘Rasa’ is used. ‘Rasibhavana’ also refers to the ability of Bhasma to assimilate in the Rasa i.e. nutrient fluid circulating inside the body after administration.


The term indicates that metals after getting converted into ‘Bhasma’ behave just like Mercury. In other words pharmaceutically they become equally effective as Mercury.



Importance of Mercury in the Ayurvedic pharmaceutics is evident from the fact that the name of pharmaceutical science related to minerals and metals is derived from the name of the Mercury itself. This importance is attributed to Mercury on account of its possession of unique physical, chemical and pharmaceutical characteristics.

Mercury being the most important one in the metal used in Rasa Sastra, other metals and minerals are also used for treatments.

  1. Rajata/ Silver

Rajata (Silver), another noble metal like gold, also attracted the attention of the ancient Acharyas. The use of silver in therapeutics dates back to the period of Charaka and his contempories. Though, its therapeutic applications are not as extensive as other metals like Tamra or Loha, the ancient classics reveal that silver also enjoyed an important place in Ayurveda therapeutics.

Various useful formulations of ‘Rajata’ are: Balya, Rasayana, Medhya, Ayushya, Ojo Vardhaka, Vayah sthapaka etc.

  1. Tamra (Copper)

Formulations of ‘Tamra’ are useful in a wide range of diseases like Krimi (worm infestation), Sthaulya (Obesity), Arsha (Hemorrhoids), Ksaya (Tuberculosis), Pandu (Anemia), Kusta (Skin diseases), Swasa, Kasa, Amlapitta, Sotha, Sula, Yakrit Roga and Grahani dosha etc.

In addition, Charaka advocates the use of Tamra Patra (copper vessels) in several pharmaceutical procedures.

Read the benefits of drinking water in Copper vessels here – Health Benefits of drinking water in Copper vessel

  1. Aayasa or Loha (Iron)

During the period of Charaka, it was used in different dosage forms named Curna, Vati, Avaleha, Varti, Asavarishta etc. either for external or internal administration in a number of pathological manifestations. Iron compounds were particularly employed in diseases suchas anaemia and other debilitating conditions, where functions of hemopoitic systems are disturbed and the blood has consequently become deficient in iron. Rasa Shastra classics explain that Loha is par excellence a rejuvenator as it stimulates functional activity of all the organs, promotes life, strength, destroys a number of diseases, and acts as a restorative.


There are so many other metals and minerals described in classics.

Emphasis is given to purification of metals and their conversion to micro-fine powders by following specified guidelines, processes which were termed ‘Ayaskriti′. Charaka suggest using these metallic preparations with great authority, stating them to be safe and efficacious if used judiciously. He also emphasizes that great caution is needed when using such metallic powders in therapeutics.


Acharyas has also mentioned the toxic effects of improperly processes metals and minerals. For example, if Mercury is used without proper purification it can cause Skin disorder, Dyspepsia, Loss of immunity, Vomiting, Loss of Taste, Sluggish Movements, Burning sensation and even death.

Therefore, it is important that Herbo-mineral preparations should be taken under the prescription of registered Ayurveda doctors.


References –

  • Galib, Barve, M., Mashru, M., Jagtap, C., Patgiri, B. J., & Prajapati, P. K. (2011). Therapeutic potentials of metals in ancient India: A review through Charaka Samhita. Journal of Ayurveda and integrative medicine, 2(2), 55–63. doi:10.4103/0975-9476.82523
  • Savrikar, S. S., & Ravishankar, B. (2011). Introduction to ‘Rasashaastra’ the Iatrochemistry of Ayurveda. African journal of traditional, complementary, and alternative medicines : AJTCAM, 8(5 Suppl), 66–82. doi:10.4314/ajtcam.v8i5S.1