Table of alchemical symbols. These and other symbols are common throughout alchemical literature and were used to denote some elements and compounds until the 18th century. While notation like this was mostly standardized, style and symbol varied between alchemists.
Basilius Valentinus. “A Table of Chymicall [Chemical] & Philosophicall [Philosophical] Charecters [Characters] with Their Significations as They Are Usually Found in Chymicall [Chemical] Authors Both Printed & Manuscript.” In The Last Will and Testament of Basil Valentine. London, England, 1671. https://digital.sciencehistory.org/works/9306sz691.