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Tyrants of the Tigris & euphrates
248
‘Abbasid Caliphate
Gold Dinar, AH 208
temp. al-Ma’mun ‘Abd Allah, ‘Abbasid Caliph, AH 194-218/AD 810-833
SICA-3, 233; BMC I, 260; A 222A.1. Extremely Fine.
No mint name (Madinat al-Salam). Kalima at center, double obverse marginal legends with Qur’an
30:4-5 (“to Allah belongs the command before and after, and in that day the believers shall rejoice in the
victory of Allah”) in outer margin and date formula in inner margin; Reverse, continuation of Kalima,
“lillah” above, Qur’an 9:33 in margin.
Al-Ma’mun (AH 194-218/ AD 810-833) was the son of Harun al-Rashid from a Persian mother. His
greatest achievement was the creation of the “House of Wisdom” in Baghdad which became the center
of exploration in mathematics, philosophy, medicine and astronomy. Muhammad al-Khwarizmi, the
Persian mathematician, is considered the founding father of algebra as a discipline. Crucial to al-Khwar-
izmi’s algebra was the incorporation of “zero” from the Indian numeric system into the Arabic numerals
which we still use today. The English word “algorithm” derives from the name al-Khwarizmi. Jabir ibn
Hayyan, the great Persian polymath born in Tus, is credited as a father of modern chemistry through
his work in alchemy. In his Dictionary of 1755, Dr. Samuel Johnson ascribed the origin of the English
word “jibberish” to the memory of Jabir, whose voluminous works were often obscure and difficult to
understand.