Saturn scythe

This Mercury is an ardent water, which has the power of dissolving all the composites, minerals and stones. And all that which resists other solvents, or strong waters, can be dissolved by the Scythe of Old Saturn which has caused the name of Universal Solvent to be given to it. 

SCYTHE OF SATURN — An expression made use of by the Philosophers in reference to the Fixed Part of the Matter of the Work which fixes the volatility of the Mercury of the Sages. 

The alchemists used the sign to denote lead, as has already been mentioned the curved portion suggests a connection between lead and silver. Lead was under the influence of Saturn and the symbol was often called the scythe of Saturn. In consequence of the high density of the metal the term saturnine became synonymous with heavy, dense, or dull-witted. Minium or red lead was known as saturnine red. 

---