Historical clue formulations

• Something tickled on a piano — 2026-05-21
• Shade of off-white — 2026-03-11
• Elephant tusk material — 2025-10-13
• Warm shade of white — 2025-06-01
• Soap that's said to be "99 44/100% pure" — 2023-05-01
• Word before Coast or tower — 2023-04-04
• ___ tower — 2022-10-01
• Highbrow tower material? — 2022-01-25
• Bygone artist's medium — 2019-10-18
• Tower construction material — 2019-02-24
• Common wedding dress color — 2017-07-07
• Shade of white — 2017-05-21
• Key ingredient? — 2017-02-03
• Something the U.S. government bans the sale of — 2016-09-28
• Bathroom bar — 2016-06-26
• ___-billed woodpecker — 2015-06-28
• Ebony's partner — 2015-02-23
• Piano key material, once — 2013-12-23
• White shade — 2012-12-30
• Material in old mah-jongg sets — 2011-12-18
• Off-white shade — 2010-12-25
• "99 and 44/100% pure" soap — 2010-05-18
• "It floats" sloganeer — 2008-07-30
• White key, informally — 2008-06-18
• Old piano key material — 2008-04-28
• Key component — 2007-09-13
• Some contraband — 2007-08-12
• Shade of white — 2006-05-17
• Piano bar — 2005-12-17
• Composition of some towers — 2005-12-03
• Key material — 2004-09-01
• Off-white — 2004-02-23
• Subject of a commercial trade ban — 2004-02-07
• Procter & Gamble brand — 2003-12-18
• Whitish — 2003-11-02
• Valuable dentine — 2003-06-15
• Off-white — 2002-05-17
• Old piano key material — 2001-12-17
• Poacher's haul — 2001-07-24
• Scrimshaw medium — 2001-05-19
• Key material — 2001-01-28
• Old artificial leg material — 2000-01-02
• Key material — 1999-11-30
• Creamy white — 1998-01-14
• Banned article of trade — 1997-06-18
• Walrus tusks — 1995-11-13
• Procter & Gamble brand — 1995-01-08
• Shade of white — 1994-06-02
• Shade of white — 1994-04-04
• Scrimshaw medium — 1994-03-25