Prussian blue was synthesized for the first time in the beginning of the 18th century. It's a complex compound which is dark blue pigment. It is used to make paints also in medicine it's an antidote for

Kimiya-yi sa'ādat (The Alchemy of Happiness) – a text on Persian Islamic philosophy and spiritual alchemy by Al-Ghazālī (1058–1111). Alchemy is a philosophical and protoscientific tradition practiced