Historical clue formulations

• ___ block — 2021-03-14
• Building block makeup — 2018-01-26
• Fireplace remnant — 2011-01-25
• Bit of air pollution — 2010-08-15
• Remnant of a burned coal — 2010-04-06
• Makeup of some blocks — 2005-07-23
• Basic building unit — 2003-08-14
• Kind of block — 1999-10-03
• Hot coal — 1995-12-16