Anno Lucis

Anno Lucis is a calendar system used in the fraternity of Freemasonry. The name is in latin which translates to "Year of Light", and refers to the biblical account of the creation of the universe ("And God said, 'Let there be light' and there was light"). Often seen on Masonic certificates and plaques, especially those commemorating the date that building's foundation was laid, the calendar is a simplification of the Anno Mundi calendar created by Bishop Ussher (1581-1656) who established the year 4004 B.C. as the date of the biblical creation of the Earth. The date Anno Lucis counts years from 4000 B.C. To convert a modern date to Anno Lucis, therefore, one simply adds 4,000 to the year under the common Anno Domini system (for instance the year 2007 A.D. converts to 6007 A.L.)
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