Mercury chloride or Sublimation (alternate #2)

 Jesse Brauner
Mercury chloride or Sublimation (alternate #2)

Resembling a combination of the signs for Libra and Mercury, this symbol is one of several alchemical markings related to sublimation.

Sublimation is a chemical process by which a substance transitions from a solid form directly into a gaseous form, without passing through an intervening liquid form. For full details of this process, see the symbol for 'Sublimation (phase transition)'.

This particular family of symbols can also represent Mercury chloride, a substance that can be sublimated very easily.