The Modern Birthstones for those born in September is the Sapphire.

The Traditional Birthstones for those with a Birth Month of September are both Sapphire and Peridot.

"... A maiden born when autumn leaves Are rustling in September's breeze,
A Sapphire on her brow should bind;
To bring her joy and peace of mind. ..."(1)

The 15th-20th Century Birthstone for September was Lapis Lazuli,(Blue), Diamond (White, Clear), Chrysolite...

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