Language:
كتاب الزكاة
24
Obligatory Charity Tax (Zakat)
(32)
Chapter: The Zakat of silver
(32)
باب زَكَاةِ الْوَرِقِ

Narrated Abu Sa`id Al-Khudri:

Allah's Messenger (ﷺ) said, "There is no Zakat on less than five camels and also there is no Zakat on less than five Awaq (of silver). (5 Awaq = 22 Fransa Riyals of Yemen or 200 Dirhams.) And there is no Zakat on less than five Awsuq. (A special measure of food-grains, and one Wasq equals 60 Sa's.) (For gold 20, Dinars i.e. equal to 12 Guinea English. No Zakat for less than 12 Guinea (English) of gold or for silver less than 22 Fransa Riyals of Yemen.)

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ عَمْرِو بْنِ يَحْيَى الْمَازِنِيِّ، عَنْ أَبِيهِ، قَالَ سَمِعْتُ أَبَا سَعِيدٍ الْخُدْرِيَّ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ لَيْسَ فِيمَا دُونَ خَمْسِ ذَوْدٍ صَدَقَةٌ مِنَ الإِبِلِ، وَلَيْسَ فِيمَا دُونَ خَمْسِ أَوَاقٍ صَدَقَةٌ، وَلَيْسَ فِيمَا دُونَ خَمْسَةِ أَوْسُقٍ صَدَقَةٌ ‏"‏‏.‏
Reference : Sahih al-Bukhari 1447
In-book reference : Book 24, Hadith 50
USC-MSA web (English) reference : Vol. 2, Book 24, Hadith 526
  (deprecated numbering scheme)