The Materia Medica of the Hindus, compiled from Sanskrit Medical Works c4.s6.12

c4.s6.12

2. *Rasakarpura*. The white preparation is the *Rasakarpura* or perchloride of mercury. Several processes are given for preparing it; one is as follows.² Take of mercury and chalk equal parts, and rub them together till the globules disappear. Rub this mixture of chalk and mercury with *pánsu* (salt obtained from saline earth) and the juice of *Euphorbia nereifolia* (*snuhi*) repeatedly. Enclose in a covered crucible and heat it within a pot full of rock salt. The perchloride of mercury will be deposited in the shape of a pure white powder under the lid of the crucible. The *Bhāvaprakāsa* gives the following process for its preparation.³ Take of purified