Historical clue formulations

• Wear down — 2019-04-21
• Wear away — 2018-01-23
• Wear down — 2017-04-20
• Use a rasp on — 2008-01-14
• Rub down — 2006-06-24
• Wear away — 2006-01-15
• Rub — 2002-12-22
• Wear down — 2002-07-06
• Rub down — 2002-01-06
• Rub off — 2001-06-10
• Rub down — 2001-06-08
• Rub — 2000-04-16
• Rub — 2000-02-06
• Wear off — 1998-06-14
• Roughen — 1996-01-12
• Wear away — 1995-11-02
• Rub — 1994-08-18
• Scrape — 1994-05-05
• Wear away — 1994-01-20
• Wear away — 1993-12-26