What are the conditions under which a silver mend (Dabba) on a utensil is permissible?

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A mend made of silver on a utensil is permissible under three conditions. First, the silver must be minor (yaseer). Second, the mend must be silver; gold is never permissible for mends, whether minor or extensive. Third, the mend must be made for a necessity or benefit, such as repairing a crack or fissure, even if another material could suffice. Those who permit silver mends include Sa'id ibn al-Musayyab, Maysarah, Zadhan, Tawus, Al-Shafi'i, Abu Thawr, Ibn al-Mundhir, the Ahl al-Ra'y, and Ishaq. Evidence supporting this leniency includes the precedent set by 'Umar ibn 'Abd al-'Aziz, who placed his mouth between two silver mends. Furthermore, the Prophet, peace be upon him, had a drinking cup mended with a silver chain, which serves as justification for minor silver work like mending a crack, similar to the permissibility of a silver ring.