Was light separated from darkness on Day 1 or Day 4?

asked by Eric

On day one, the word used for day is “yom”, its the first occurance in the Bible and specifically describes a single solar day.

Genesis 1:4

4 God saw that the light was good, and he separated the light from the darkness. {4} {5}5 God called the light “day,” and the darkness he called “night.” And there was evening, and there was morning —the first day.