Know Your Birthstones

It is sometimes also called birthday stone (cf. infra; but that word is, confusingly, sometimes used as a synonym for an anniversary gift, which is related to the recipient's age, that is, year of birth).

There have been many different sets of birthstones used throughout history and in different cultures. In 1912, in an effort to standardize them, the American national association of jewelers,Jewelers of America, officially adopted the following list; it is currently the most widely used list in the United States and many other locations, including Australia and Thailand. Some alternates have been adopted to be a less expensive substitute for a cut stone.

Traditional Modern
Month Birthstone(s) Birthstone(s)
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January garnet garnet
February amethyst amethyst
March bloodstone jasper aquamarine

April diamond, sapphire diamond
May emerald, agate emerald
June alexandrite, emerald moonstone, pearl
July ruby, onyx ruby
August sardonyx, sapphire peridot
September sapphire, peridot sapphire
October tourmaline, pearl opal, tourmaline
November citrine, topaz topaz, citrine
December zircon, lapis lazuli turquoise, tanzanite, blue topaz

Tanzanite was added to December by the American Gem Trade Association in 2002. Most organizations do not recognize tanzanite as a December birthstone, however, and the AGTA's move to make it a December birthstone has generally been viewed as a marketing ploy

Origins

The birthstone seems to originate from Biblical times. The Breastplate of Aaron, referred to in Exodus 39:10-14:

10 Then they mounted four rows of precious stones on it. In the first row there was a ruby, a topaz and a beryl;

11 in the second row a turquoise, a sapphire and an emerald;

12 in the third row a jacinth, an agate and an amethyst;

13 in the fourth row a chrysolite, an onyx and a jasper. They were mounted in gold filigree settings.

14 There were twelve stones, one for each of the names of the sons of Israel, each engraved like a seal with the name of one of the twelve tribes.

The precise list of birthstones however can be found in Revelation 21:19-20 where the foundation stones of the new Jerusalem are listed, in the order of the Roman calendar:

14 And the wall of the city had twelve foundations, and in them the names of the twelve apostles of the Lamb. . .

19 And the foundations of the wall of the city were garnished with all manner of precious stones. The first foundation was jasper; the second, sapphire; the third, a chalcedony; the fourth, an emerald;

20 The fifth, sardonyx; the sixth, sardius; the seventh, chrysolyte; the eighth, beryl; the ninth, a topaz; the tenth, a chrysoprasus; the eleventh, a jacinth; the twelfth, an amethyst.