Sahih Muslim Book 41, Hadith Number 6997.
Chapter : Story of Ibn Sayyid.
This hadith has transmitted on the authority of Abu Sa’id that Allah’s Messenger (may peace be upon him) asked Ibn Sa’id about the earth of Paradise. Thereupon he said: Abu’l-Qasim, It is like a fine white musk, whereupon he (the Holy Prophet) said: ‘You have told the truth.