Musannaf Ibn Abi Shaybah 24278 — A man who pledges something

Sayyiduna Ali (may Allah be pleased with him) said: If the pledge is worth more than what it was pledged for and it perishes, then it is lost, because he is a trustee with regard to the excess. And if it is worth less than what it was pledged for and then perishes, the pledger will return the difference.