Historical clue formulations

• White part of an orange — 2026-08-24
• Essence — 2026-05-14
• Oft-discarded part of an orange — 2026-02-24
• Bitter part of an orange — 2022-12-26
• Crux — 2021-06-26
• Crux of the matter — 2021-03-27
• The white stuff in an orange — 2019-12-16
• Bitter part of an orange — 2019-11-25
• Essential part — 2019-06-25
• Heart — 2018-06-02
• Crux — 2018-01-11
• Essential element — 2016-08-27
• Substance — 2016-04-30
• Soft plant tissue — 2015-01-12
• Essence — 2014-12-01
• Heart of the matter — 2014-03-25
• Heart of the matter — 2013-10-02
• Heart of the matter — 2012-03-20
• Essence — 2010-01-17
• Central part — 2008-04-21
• Core — 2005-10-29
• Tropical helmet material — 2005-10-16
• Nitty-gritty — 2004-06-23
• Heart or soul — 2003-07-12
• Central part — 2003-05-06
• Kind of helmet — 2002-05-02
• Marrow — 2002-01-16
• Core — 2001-12-21
• Meat — 2001-01-05
• Essence — 1998-05-25
• Heart of the matter — 1997-07-27
• ___ helmet (safari wear) — 1997-03-03
• Essence — 1996-09-04
• Core — 1995-09-10
• Material for a topi — 1994-07-21