Volume 2 · Book 24 · Hadith 561
Narrated Abu Said Al-Khudri : The Prophet said, "There is no Zakat on less than five Awsuq (of dates), or on less than five camels, or on less than five Awaq of silver." (22 Yameni Riyals Faransa).
— Sahih Bukhari, Volume 2, Book 24: Obligatory Charity Tax (Zakat), Hadith #561