‘A crescent shape is a symbol or emblem used to represent the lunar phase in the first quarter (the "sickle moon"), or by extension a symbol representing the Moon itself.
It is used as the astrological symbol for the Moon, and hence as the alchemical symbol for silver. It was also the emblem of Diana/Artemis, and hence represented virginity. In Roman Catholic Marian veneration, it is associated with the Virgin Mary.
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