Historical clue formulations

• Surface of a well-used wok — 2026-09-03
• Green film on copper, e.g. — 2026-05-07
• Green coating on a statue — 2024-11-25
• Green layer on the Statue of Liberty — 2021-05-04
• Coating produced by oxidation — 2021-02-12
• An antique might have one — 2020-05-24
• Green outer layer of a statue — 2019-11-05
• Film about a statue? — 2012-05-22
• It makes the Statue of Liberty green — 2012-01-06
• Antique asset, often — 2010-10-14
• Film about the Statue of Liberty? — 2010-02-27
• Metal coating — 2006-03-28
• Sheen formed with age — 2004-08-22
• Old film — 2004-06-24
• Film — 2001-12-01
• Ornamental film — 1998-12-13
• Verdigris, for one — 1998-10-24
• Verdigris — 1996-03-27