It is said that birthstones came to be when the Jewish historian Josephus made a connection between the twelve stones on Aaron’s breastplate and the twelve months in a year and its respective Zodiac Signs.
This at least, is one of the more popular background stories on its Western origin, but there are at least a dozen others claiming to have propagated the idea of birthstones. Nowadays there is still no clear standard list of which birthstone corresponds to what month, and the correspondence seems to largely depend on personal preference. Currently however, most jewelers the world over follow a list similar to what can be found on this infographic created by online jeweler Brilliance.com.
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