In the document of the Messenger of Allah ﷺ and in the document of Umar concerning charity, it is stated that nothing is taken from gold until it reaches twenty Dinars. Once it reaches twenty Dinars, half a Dinar is due on it. As for silver, nothing is taken from it until it reaches two hundred dirhams. Once it reaches two hundred dirhams, five dirhams are due on it.
إن في كتاب رسول الله ﷺ وفي كتاب عمر في الصدقة: أن الذهب لا يؤخذ منه شيء حتى يبلغ عشرين دينارا، فإذا بلغ عشرين دينارا ففيه نصف دينار. والورق لا يؤخذ منه شيء حتى يبلغ مائتي درهم، فإذا بلغ مائتي درهم ففيها خمسة دراهم.
Abu Ubayd narrated it in his book al-Amwal (p. 559), from Yazid bin Harun, from Habib bin Abu Habib, from Amr bin Haram, from Muhammad bin Abdul-Rahman al-Ansari, who said, and then he related it. Its chain of transmission is sahih. Amr bin Haram is al-Azdi al-Basri, one of the men found in Muslim's Sahih. In form it appears to be a mursal report, since Muhammad bin Abdul-Rahman al-Ansari was a follower (tabii), but its ruling carries the force of a raised report, because he found the letter of the Messenger of Allah ﷺ concerning the alms among the descendants of Amr bin Hazm, and the letter of Umar bin Khattab among the descendants of Umar, as he stated in what Abu Ubayd also related in al-Amwal (p. 497), with the same chain of transmission, from Muhammad bin Abdul-Rahman al-Ansari, who said,"When Umar bin Abdul-Aziz became caliph, he sent to Madinah seeking the letter of the Messenger of Allah ﷺ concerning the alms and the letter of Umar bin Khattab." He said, "So we copied it out for him." He said, "Amr bin Haram told me that he had asked Muhammad bin Abdul-Rahman to copy out for him what was in those two letters, and he copied out for him what was in this letter concerning the alms due on camels, cattle, sheep, gold, silver, dried dates - or fresh dates - grain, and raisins."He then related the hadith in full. It contains no mention of the minimum threshold for gold and silver. Abu Ubayd said, "He then went on to mention the remaining categories of alms in this hadith, and they will come in their proper places, Allah willing." End of quote.