Who knows three hundred twelve?
?שנים עשר ושלוש מאות - מי יודע
In the spirit of the song "Echad - mi yodeya", please post interesting and significant Jewish facts about the number 312.
Don't dwell on lazy gematria; it's bad to get caught up in something so dry.
Check out mi-yodeya-series for the previous three hundred eleven entries in this ongoing series.
Please include sources for your information wherever possible, as with all other answers on this site.