[34] Now at that time the group-of-six bhikkhus used bowls of various kinds—a bowl made of gold, a bowl made of silver. People looked down upon them, criticized them, and spread it about, saying: "… just like householders who enjoy sensual pleasures." … They reported this matter to the Blessed One. …
"Bhikkhus, a bowl made of gold should not be used; a bowl made of silver should not be used; a bowl made of gems should not be used; a bowl made of beryl should not be used; a bowl made of crystal should not be used; a bowl made of bronze should not be used; a bowl made of glass should not be used; a bowl made of tin should not be used; a bowl made of lead should not be used; a bowl made of copper should not be used. Whoever should use one commits an offense of wrong-doing (dukkaṭa). Bhikkhus, I allow two bowls: an iron bowl and a clay bowl."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.