The tradition of associating certain gemstones with months of the year dates back thousands of years. While some months are associated with a single birthstone, many months are now considered to have multiple birthstones. Which gemstones are designated as birthstones for a given month can vary somewhat between cultures and traditions, but there are several widely recognized modern birthstone lists.
The traditional birthstone list
The traditional birthstone list, which originated in Poland in the 18th or 19th century, assigns a single birthstone to each month. This list became widely popular in the United States in the early 20th century. The traditional birthstone monthly assignments are as follows:
| Month | Birthstone |
| January | Garnet |
| February | Amethyst |
| March | Aquamarine |
| April | Diamond |
| May | Emerald |
| June | Pearl |
| July | Ruby |
| August | Peridot |
| September | Sapphire |
| October | Opal |
| November | Topaz |
| December | Turquoise |
As this list assigns only a single birthstone per month, the answer is no – not all months have 2 birthstones on the traditional birthstone list.
Modern birthstone lists
In 1912, the American National Association of Jewelers (now Jewelers of America) adopted an expanded list of birthstones, assigning more than one stone for most months. This was an effort to standardize birthstones across the jewelry industry and give consumers more choices. Additions were made in 1952, bringing the total stones on the modern birthstone list to 12 (one for each month of the year).
The key differences between the traditional and modern birthstone lists are:
- January has the additional birthstone of garnet
- March has aquamarine as well as bloodstone
- May has emerald as well as chrysoprase
- June has 3 stones – pearl, alexandrite, and moonstone
- August has peridot as well as spinel
- October has opal as well as tourmaline
- December has turquoise as well as tanzanite and zircon
Other widely recognized modern birthstone lists include the mystical birthstone list, which assigns a different stone for each month based on its symbolic and healing properties, and the Ayurvedic birthstone list used in Hindu astrology, which also assigns multiple stones per month.
So do all months have 2 birthstones?
Based on the modern birthstone lists that assign multiple stones for most months of the year, the answer is yes, all months have at least 2 designated birthstones. The traditional birthstone list is the only one that assigns a single stone per month.
Here is a comparison of the number of birthstones per month on some common lists:
| Month | Traditional | Modern | Mystical | Ayurvedic |
| January | 1 | 2 | 1 | 2 |
| February | 1 | 1 | 2 | 2 |
| March | 1 | 2 | 2 | 2 |
| April | 1 | 1 | 2 | 3 |
| May | 1 | 2 | 2 | 2 |
| June | 1 | 3 | 2 | 2 |
| July | 1 | 1 | 2 | 3 |
| August | 1 | 2 | 2 | 2 |
| September | 1 | 1 | 2 | 2 |
| October | 1 | 2 | 2 | 2 |
| November | 1 | 1 | 2 | 2 |
| December | 1 | 3 | 2 | 2 |
In summary, while the traditional birthstone list assigns a single stone per month, most modern birthstone lists assign multiple stones for each month of the year. So it is generally accurate to say that all months have at least 2 designated birthstones in common practice today.
Conclusion
The tradition of birthstones originally involved assigning a single gemstone to each month, as seen in the historical traditional birthstone list. However, modern birthstone lists have expanded this tradition by designating multiple stones for most months. This provides people more options to find a birthstone with personal meaning. The modern birthstone lists, including versions published by jewelers’ associations, astrologers, and spiritual practitioners, all assign 2 or more stones for every month. So the answer is yes – due to these modern lists, all 12 months of the year now have at least 2 associated birthstones.