Mole Day (International observance)

Mole Day is an unofficial holiday celebrated among chemists, chemistry students, and chemistry enthusiasts on October 23 between 6:02 a.m. and 6:02 p.m., making the date 6:02 10/23 in either MDY or YMD date formats. The time and date are derived from the Avogadro constant, which is approximately 6.02×10²³, defining the number of particles (atoms or molecules) in one mole (mol) of substance, one of the seven base SI units.

Lists of holidays by various categorizations.