Ring Sizer Birthstone by month: a chart for all 12 months
January is garnet, February amethyst, March aquamarine, April diamond, May emerald, June pearl, alexandrite or moonstone, July ruby, August peridot or spinel, September sapphire, October opal or tourmaline, November topaz or citrine, December tanzanite, turquoise or zircon. Most calendars only list one stone per month, so it is easy to forget some months have three options.
Birthstone by month chart
Hardness runs on the Mohs scale, 1 to 10, same numbers the app uses. It's not a trivia stat — a ring takes far more knocks than a pendant ever will, so a soft stone in a ring needs a different level of care than the same stone in a necklace.
| Month | Birthstone | Hardness (Mohs) |
|---|---|---|
| January | Garnet | 7.0 |
| February | Amethyst | 7.0 |
| March | Aquamarine | 7.5 |
| April | Diamond | 10.0 |
| May | Emerald | 7.5 |
| June | Pearl, Alexandrite, Moonstone | 2.5 / 8.5 / 6.0 |
| July | Ruby | 9.0 |
| August | Peridot, Spinel | 6.5 / 8.0 |
| September | Sapphire | 9.0 |
| October | Opal, Tourmaline | 5.5 / 7.0 |
| November | Topaz, Citrine | 8.0 / 7.0 |
| December | Tanzanite, Turquoise, Zircon | 6.5 / 5.5 / 7.5 |
How to open the birthstone calendar in the app
- Open Gemstones from the home screen.
- Tap View Birthstone Calendar. The list switches to a month-by-month view with each stone's colour.
- Tap a stone to open its card with hardness, description and Care & Cleaning tips.
- Tap Show All Gemstones to go back to the full list.
The calendar itself is entirely free to browse. Diamond, ruby, sapphire and emerald open their full cards too, same with moissanite, which has no month at all. Everything else is locked behind Premium, which is where this guide hits its limit — June's three stones can be named here, but you'll need to pay to read what the app says about caring for alexandrite specifically.
June birthstone: three choices
June wins on variety. Pearl sits at 2.5, the softest stone in the whole set, and the app is blunt about it: no chemicals at all, not even perfume or hairspray drifting near it. Alexandrite jumps to 8.5 and does the party trick of looking green in daylight and red under incandescent light. Moonstone lands in between at 6.0, fine for occasional wear or a protective setting but not an everyday ring.
December birthstone: tanzanite, turquoise or zircon
December gets three stones too. Tanzanite (6.5) is an occasional-wear stone, sensitive to heat. Turquoise (5.5) is porous — soft, dry cloth only, nothing with perfume or sunscreen anywhere near it. Zircon (7.5) is harder but chips at the edges if you're rough with it. Worth saying plainly: zircon is a natural mineral, nothing like cubic zirconia despite the similar name.
Choosing a birthstone for a ring you wear every day
- Stones rated 8 and above in the table (diamond, ruby, sapphire, alexandrite, spinel, topaz) handle daily wear well.
- Stones around 7 (garnet, amethyst, aquamarine, emerald, tourmaline, citrine, zircon) are fine with some care; emerald in particular is more fragile than its rating suggests because of its inclusions.
- Stones below 7 (pearl, moonstone, peridot, tanzanite, opal, turquoise) suit occasional wear or a protective setting.
- Whatever the stone, get the ring size right first: some settings make resizing harder.
Questions and answers
Why do some months have more than one birthstone?
Does the app explain birthstone meanings?
What is the April birthstone?
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- How to clean and care for a ring at home
- Compare two ring sizes: how big is the difference?
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