Sayyiduna Anas (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "Clean yourselves with three stones, and with earth when one does not find stones; and a thing with which one has cleaned oneself once should not be used for cleaning a second time."
Abu Ahmad bin Adi said: Most of what this Ibrahim bin Abi Humayd narrates, no one corroborates him in it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 542