How do I solve 8 down in Times Cryptic 29573?

Question

Accepted Answer

8 down reads "“Very good” diamonds are cut, put in place — by me?" (8 letters); the answer is LAPIDARY. It's a double-definition clue: two separate definitions of the same word sit side by side. No wordplay split and no indicators — both halves of the clue define the answer. The full step-by-step breakdown is on this page.

“Very good” diamonds are cut, put in place — by me? (8)

8D — “Very good” diamonds are cut, put in place — by me? (8) — LAPIDARY