en_tn/rev/21/21.md

pearls

beautiful and valuable white beads. They are formed inside the shell of a certain kind of small animal that lives in the ocean. See how you translated this in Revelation 17:4. (See: rc://en/ta/man/translate/translate-unknown)

each of the gates was made from a single pearl

This can be stated in active form. Alternate translation: "someone had made each of the gates from a single pearl" (See: rc://en/ta/man/translate/figs-activepassive)

pure gold, like transparent glass

The gold was so clear that it is spoken of as if it was glass. See how you translated a similar phrase in Revelation 21:18. (See: rc://en/ta/man/translate/figs-simile)