Arabic inscriptions: "There is no God except Allah alone. He has no partner" in the central field, dot below, "In the name of Allah this dirhem was struck at Medinat al-Salam in the year one hundred sixty two" in the margins, all within a triple border with three double annulets and three plain annulets/ "Allah is one, Allah is eternal. He begets not neither is he begotten" in the central field, "Mohamed is the prophet of Allah whom he sent with guidance and the religion of truth that he may make it victorious over every other religion", all within a border with five annulets. Minted in 162 AH = 778 AD, mint of Medinat al-Salam. 24mm, 2.87 grams. Mitchiner WIS 159v; Lavoiux #729; S. 215.1.
This is a beautiful high quality coin showing original luster. It was reportedly found in Spain in a large hoard of Abbasid coins.
Muhammad ibn Mansur al-Mahdi (ruled 775-785), was the third Abbasid Caliph. He succeeded his father, al-Mansur. Al-Mahdi, whose name means "Rightly-guided" or "Redeemer", was proclaimed caliph when his father was on his deathbed.