Ayurveda is the most ancient therapy which was practiced by our Acharya long back ago. Among all the therapeutic
measures used by Vaidya, Rasashatra is considered as the backbone of all the treatments. Most commonly practiced Dravya in
Rasashastra are Parad (mercury), Gandhak (sulphur), Abhrak (Mica), Shilajatu (black bitumen) and so on. The main purpose
of Rasashastra is said to be Dehvad which was later on carried forward to the level of Lohvada and Chikitsavad. To achieve this
along with Parad, Gandhak was most popularly practiced by Rasacharya. Gandhak was very well known Dravya from Samhita
time but after 8
th century there was no any Dhatukarma which was formulated without Gandhak. In the text Rasatarangini six
different Shodhan processes were mentioned out of which special emphasis will be given to fifth Shodhan method that is by
Urdhvapatan using Damru Yantra. Gandhak obtained by this process is considered as the purest form.
