It is narrated from Sayyiduna Ya'la bin Murrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever finds a small lost item, a rope, a dirham or something similar, let him announce it for three days; and if it is more than that, let him announce it for six days."
Only Umar bin Abdullah bin Ya'la narrated it; Yahya bin Ma'in declared him da'if (weak), and Jarir bin Abd al-Hamid and others accused him of drinking wine.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب اللقطة / 12100