The alchemical symbol for sulphur, the soul, and the sun, associated with the fire and brimstone of Hell. Can also be known as a 'Leviathan Cross'. Also known as the Diamond King's symbol. The Double cross symbolizes protection and balance between persons.
The infinity sign underlines the constant and infinite nature and most likely symbolizes the eternal universe, this may have been used by Anton LaVey in The Satanic Bible to as a mockery of the cross, to show that humans are their own centrum of balance, and truth. This is what the ideology of Anton LaVey and the followers of the Church of Satan believe, and this is what this symbol represents in this association.
An upside-down crucifix is also a symbol embraced by Satanists. That confuses some people as it is seen as the Petrine Cross or "The Cross of St. Peter" since, according to Origin of Alexandria, Simon Peter was crucified upside down. However, turning a symbol like a cross upside-down is symbolic on it's own and the interpretation of doing so differs among Catholics and Satanists.
In Alchemy, the Leviathan's cross is a symbol for sulfur, which is one the three essential elements of nature.
In Asia, its name is the Brimstone Symbol.
The Leviathan Cross was created by The Knights Templar. The symbol was then adopted by Anton LaVey, founder of the Church of Satan. Previous associations with the cross and Satanic foundations are unable to be identified.