What is alchemy symbol sulfur?

The alchemy symbol for sulfur, also known as brimstone, consists of a triangle atop a cross. The triangle represents fire and the upward movement of sulfur in the alchemical process, while the cross symbolizes matter and the four elements. Sulfur was considered a vital component in alchemical transmutation, representing the active, male principle and often associated with the sun. It was also believed to be essential for the creation of medicines and the philosopher's stone, a mythical substance said to have the power to transform base metals into gold and grant immortality.