Rasashastra is Ayurvedic pharmaceutics, which deals with the drugs of mineral origin, their varieties, characteristics, processing techniques, properties and their therapeutic uses.

The actual development of Rasashastra as an independent branch of learning and therapy was started from the eight century A.D. and onwards. But before that period, in Charaka Samhita and Sushruta Samhita also, there is a good deal of description of parthiva type of drugs, their processing techniques and their principles.

As modern science has proved, mercury, metals and minerals produce some toxic effects also. The review of ancient rasa literature revealed that the ancient scholars had emphasized this fact and they took care of this point by evolving specific methods for the shodhana process.

There are many processes in Rasashastra, which play a very important role in making the Ayurvedic metallic and mineral preparations free of toxicity and in making them highly absorbable into the system as compared to the metallic and mineral compounds prepared by modern chemical methods.