The minimum of nisab for gold is twenty dinars owned for one year. Its due is a quarter of a tenth, that is, half a dinar. For any amount over twenty dinars, a quarter of a tenth is levied upon it. ‘Ali reported that the Prophet, upon whom be peace, said: “There is nothing upon you in gold, until it reaches twenty dinars. Thus, if you have twenty dinars at the end of the year, then there is half a dinar levied on it [as zakah]. Any additional amount will be calculated in this manner. There is no zakah on property until it has been owned for one year.” This hadith is related by Ahamd, Abu Dawud, and al-Baihaqi. Al-Bukhari grades it authentic and alHafizh verified it.
Zuraiq, the Fazarah clan’s protÃ©gÃ©, reported that ‘Umar ibn ‘Abdulaziz wrote to him after he became caliph: “Take what passes by you of the commerce of the Muslims – those who trade with their properties – a dinar for each forty dinars. From that which is less than forty, calculate on the lesser amount until it reaches twenty dinars. If you have to take one-third of a dinar, disregard it and do not take anything on it. Afterwards, give them a written release of what you have levied from them until the year expires.” This is related by Ibn Abu Shaibah.
Malik says in his al-Muwatta’: “The uncontroversial tradition that we have is that the zakah due on twenty dinars is like the zakah due on two hundred dirhams.” Twenty dinars are equal to twenty-eight Egyptian dirhams in weight.