Historical clue formulations

• Element between copper and gallium on the periodic table — 2026-05-16
• Alphabetically last nutrient in a multivitamin, often — 2026-02-13
• Brass component — 2025-01-21
• Next-to-last chemical element alphabetically — 2023-10-24
• 97.5% of a penny — 2022-12-26
• Immunity-boosting element — 2020-09-23
• Metal in galvanization — 2020-06-07
• About 97% of the modern penny — 2019-10-29
• 30, on a table — 2018-01-13
• Portion of a penny — 2017-04-23
• Next-to-last element alphabetically — 2016-11-07
• Multivitamin ingredient — 2016-07-19
• More than a fraction of a cent — 2016-07-09
• Mineral contained in oysters — 2016-06-14
• Next-to-last chemical element alphabetically, before zirconium — 2014-11-03
• Battery element — 2014-11-02
• ___ oxide (beachgoer's protection) — 2014-08-25
• Brass section? — 2014-05-29
• Corrosion-preventing coating — 2014-05-16
• Component of brass — 2013-08-21
• 97.5% of a penny — 2011-04-27
• Major Peruvian export — 2011-04-01
• Brass component — 2010-07-21
• Calamine component — 2010-04-23
• 97.5% of a penny — 2009-11-01
• Next-to-last element alphabetically — 2009-07-13
• ___ oxide (sunscreen compound) — 2008-11-12
• Much of a penny — 2004-07-08
• Multivitamin additive — 2003-12-22
• Metal in galvanization — 2003-11-18
• Metal in some batteries — 2003-07-14
• Metal in pennies — 2002-09-03
• Brass component — 2002-05-28
• Metal in brass — 2002-03-11
• Kind of sulfide — 2001-11-29
• Brass = copper + ___ — 2001-06-25
• Brass component — 2001-02-09
• Plating material — 2001-02-08
• Galvanizing metal — 2000-11-28
• Like some plating — 1999-01-20
• Brass component — 1998-04-21
• Healthful mineral — 1998-03-23
• Element #30 — 1997-07-23
• Coating metal — 1997-06-23
• Over-the-counter cold remedy — 1997-06-17
• Vitamin additive — 1997-04-30
• Wurtzite ingredient — 1994-10-30