Historical clue formulations

• Combustible rock — 2026-07-07
• Steam engine need — 2026-05-27
• Christmas stocking filler for a naughty child — 2025-07-28
• Shade of black — 2025-01-08
• Rhyme for "soul" in "Frosty the Snowman" — 2024-12-22
• Traditional Scottish New Year's gift, representing warmth for the year to come — 2024-08-30
• *Nonrenewable energy source … and the start of an eight-step word ladder — 2024-04-22
• Combustible rock — 2023-04-25
• What Santa gives naughty children — 2022-07-18
• Rock around the Christmas tree? — 2020-09-16
• Unwanted stocking stuffer — 2019-07-08
• West Virginia resource — 2019-06-04
• Santa's "gift" for bad children — 2019-03-19
• Eyes for Frosty the Snowman — 2018-01-03
• Anthracite, e.g. — 2017-10-23
• Fuel that contributes to global warming — 2017-10-17
• Jet — 2016-09-08
• Big product of Kentucky — 2016-08-15
• Stocking stuffer — 2016-06-12
• Shade of black — 2015-07-16
• West Virginia export — 2015-04-22
• ___ black — 2015-01-25
• Fossil fuel — 2014-09-01
• Either of Frosty the Snowman's eyes — 2013-07-02
• Unwanted stocking stuffer — 2013-05-06
• ___-black — 2012-09-04
• Fossil fuel — 2012-08-27
• Bad child's stocking filler — 2011-10-25
• Unwelcome stocking stuffer — 2011-01-09
• Mine find — 2010-08-10
• Kentucky resource — 2010-08-05
• Big Utah export — 2010-02-13
• Seamy stuff? — 2009-11-13
• "Present" in bad kids' Christmas stockings — 2008-04-30
• Santa's "present" for a naughty child — 2007-06-04
• Epitome of blackness — 2007-05-06
• Shade of black — 2007-02-04
• Fuel that's shoveled — 2006-09-26
• Shade of black — 2006-07-06
• Symbol of blackness — 2005-12-28
• Fuel from a mine — 2004-09-13
• Scuttle contents — 2004-03-26
• Scuttle filler — 2003-07-23
• Kentucky resource — 2002-08-27
• Brat's stocking stuffer — 2002-03-12
• Locomotive fuel — 2001-10-16
• Scuttle's contents — 2001-05-04
• Shade of black — 2001-04-01
• Anthracite, e.g. — 2000-06-19
• Black shade — 1999-12-02