Wikipedia
Raseśvara
Raseśvara was a Shaiva philosophical tradition which arose around the commencement of Christian era. It advocated the use of mercury to make the body immortal. This school was based on the texts Rasārṇava, Rasahṛidaya and Raseśvarasiddhānta, composed by Govinda Bhagavat and Sarvajña Rāmeśvara.