"The Messenger of Allah was asked about (buying) fresh dates with dried dates, and he said to those who were around him: 'Will fresh dates decrease (in weight or volume) when they dry out?" they said Yes,' so he forbade that."
Reference: Sunan an-Nasa'i 4545 In-book : Book 44, Hadith 97 English translation : Vol. 5, Book 44, Hadith 4549
Help us gift a modern, ad-free Islamic application for the Muslim Ummah. Your donation will be recorded as Sadaqah Jariyah in your book of deeds, In Sha Allah.