Who decided the birthstones?
The list most American jewelers use was agreed at a trade meeting in 1912, and trade groups have revised it since.
Key points
- The standard American list was agreed in 1912 by the trade group now called Jewelers of America.
- Later revisions added tanzanite for December in 2002 and spinel for August in 2016.
- If your month's stone is too soft for a daily ring, the list often has an alternative.
In this article
The idea of a stone for each month is old. The list most jewelers use is barely a century old.
An old idea
The Book of Exodus describes a breastplate worn by the high priest Aaron, set with twelve stones for the twelve tribes of Israel. In the first century, the historian Josephus linked those twelve stones to the twelve months and the signs of the zodiac.
Nobody is sure which minerals the ancient names meant, and the breastplate stones do not line up with any modern list. For centuries, the customs varied from country to country and writer to writer.
The 1912 list
In 1912 the American National Retail Jewelers Association, now Jewelers of America, met in Kansas City and agreed on a standard list:
- January: garnet
- February: amethyst
- March: bloodstone or aquamarine
- April: diamond
- May: emerald
- June: pearl or moonstone
- July: ruby
- August: sardonyx or peridot
- September: sapphire
- October: opal or tourmaline
- November: topaz
- December: turquoise or lapis lazuli
Changes since
Trade groups have revised the list several times. In 1952, alexandrite was added for June, citrine for November and pink tourmaline for October, and zircon replaced lapis lazuli for December. Tanzanite was added for December in 2002, and spinel for August in 2016.
Other countries keep their own lists. In Britain, the National Association of Goldsmiths published one in 1937 that differs in several months.
Choosing
Birthstones are a convention set by jewelers, so there is no wrong choice. If the stone for your month is too soft for a daily ring, the list often has an alternative. Opal, the traditional October stone, scratches and chips easily in a ring, and pink tourmaline, October's other stone, is much harder.
Filed under Stones · September 26, 2026
