What does the cryptic crossword clue "Piece of skin torn by silver pin (6)" mean?

The wordplay uses a charade (building blocks). AG (synonym="chemical symbol, ‘silver’") + NAIL (synonym="‘pin’") = AGNAIL The answer is AGNAIL.

Piece of skin torn by silver pin (6)

Guardian Cryptic #29387 | 5 Down | 2024-05-20 flower