The branch of Ayurveda which deals with study of metals,gems and minerals.This branch also explain the uses of metals in case of various diseases.
The metals or minerals which are used in medicine formulation,where completely detoxified by various processes like by multiple heating,or cooling or adding of various herbs in to it .This process of detoxification of metals is called as Dhatu shodhan and Marana.
In ancient granthas ,mercury is described as Rasa.Hence this branch is known as Rasashatra because in this All the details knowledge about Mercury and their uses,types,kalps,suddhikaran etc all explained.
While the other metals,minerals and gems are classified in to dhatu,upadhatu,ratna,uparatna,maharasa,sadharan rasa and sudha varg
After rasa, the next important group of minerals and their importance in formulations after rasa are named as maharasa.
There are eight maharasas. They are as follows:
In rasashastra, the minerals are divided into many groups: maharasa, uprasa and sadharana rasa, dhatu, upadhatu, ratna and upratna, etc.
After maharasa comes the category of uprasa. It consists of the eight constituents:
After the classification of minerals into rasa and maharasa, the ancient alchemists divided the next category into sadharana rasa i.e. ordinary compounds which are as follows:
Dhatu includes the group containing metals like gold, silver, etc. and previously they were termed as loha varga.
The word loha originates from ‘luh’ which means ‘to extract’.
Thus all the metals are extracted from the ores and also those who extract all the diseases from the body are called metals.
The metals described are :
These are seven dhatus
The classification after dhatus is upadhatus.
There are 7 upadhatus :
Svarna makshik (Copprer pyrite)
Tutha (Copper sulphate)
Kharpar (Zinc ore)
Kasis (Ferrous sulphate)
Gairika (Red ochre)
Ratna means precious stones.
They have a great effect on the human beings and their health and have astrological importance.
Each gem has a specific effect on a particular planet and in turn on the human body.
The ancient people realizing its importance on the humans and of the curative powers have described them.
There are nine gems (navaratna) which are as follows:
Vaidurya (cat’s eye)
After the classification of gems, the stones, which were having qualities less than the gems like hardness, luster and transparency, classified into upratna.
Upratna means minor gems or semiprecious gems.
Substances containing calcium are termed as sudha.
These are grouped into a group termed as sudha varga.
This group consists of :
Churna sudha (Quick lime)
Samudraphen (Cuttle fish)
Shukti (Oyster shell)
Kukkutandatwak (Egg shell)