In this guide I hope to share a little about the history of birthstones, and some information about current accepted stones.

In the first century, Josephus, a Jewish historian, claimed a correlation between the twelve stones in Aaron’s breastplate, the months of the year, and the signs of the zodiac.
The breastplate, mentioned 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.

Revelations 21:14 & 19-20, go on to tell of the stones needed to build the foundations of a new Jerusalem.

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.

This was taken to mean the relationship of each stone to the months in the Roman calendar.

The tradition of people wearing their birthstones is thought to have become popular in 15th century Poland. Generally, people had a set of twelve stones, and wore the one corresponding to the month they were in, as it is believed to enhance the power of the stone. Not dissimilar to current thinking in crystal therapy.

In 1912 the American Association of Jewelers devised the official birthstone list. This tried to standardise the commonly accepted stones in America and Europe. However, it did not stop some of the traditional stones still being used, thankfully.

Below is a chart showing both the modern birthstones, and the birthstones from some of the older traditions.