Born on 700 Died on 800
Jabir himself says to have learned with Harbi al-Himyari, Udhun al-Himar and a monk. After this, he maintains, he joined Ja'far al-Sadiq (d. 765) who taught him the whole of alchemy. Click here for more information.
Died on 1295
In the thirteenth century the military engineer Hasan al-Rammah (d. 695 AH/1295 AD) described in his book al-furusiyya wa al-manasib al-harbiyya (The Book of Military Horsemanship and Ingenious War Devices) the first process for the purification of potassium nitrate.