Historical clue formulations

• Did some engraving — 2026-06-15
• Inscribed — 2025-11-02
• Scratched the surface? — 2022-09-07
• Like some glasswork — 2010-01-08
• Fixed for all time — 2009-08-23
• Marked permanently — 2008-04-27
• Designed like Dürer — 2004-04-28
• Deeply embedded — 2000-09-14