Birthstones by Month: A Complete Guide to All 4 Systems

A birthstone is the gem traditionally tied to the month you were born, and there isn't one single list for it — four separate systems (modern, traditional, mystical, and Ayurvedic) each assign a stone to every month, and they don't always agree. When someone asks "what's my birthstone by month," they almost always mean the modern list, the one U.S. jewelers standardized in 1912 and have updated a handful of times since. That's the list we lead with below, alongside the older traditions behind each stone. For a shorter, shopping-focused version of this same chart, see our birthstones hub.

The modern birthstone chart at a glance

Six months — March, June, August, October, November, and December — carry more than one official modern stone. The other six have a single, undisputed answer. We'll go month by month below, with the physical facts, the tradition behind each stone, and an honest note on affordable alternates where one exists.

Every month in detail

January: Garnet

Garnet isn't a single mineral but a silicate group, which is why it turns up in nearly every color except blue — though the deep red variety is what most people picture. It sits at Mohs 6.5–7.5, hard enough for daily rings. Tradition ties garnet to protection, vitality, and steadfast devotion; old travelers reportedly carried it as a "lamp stone" to light the way. It's also one of the more forgiving birthstones to shop for — durable, widely available, and priced well below the precious-gem tier.

February: Amethyst

February belongs to amethyst, the violet-to-deep-purple variety of quartz (Mohs 7) colored by trace iron and natural irradiation. In crystal tradition it's associated with calm, clarity, and a steady mind — the Greek root of its name literally means "not intoxicated," tied to old beliefs about sobriety. Major nineteenth-century deposits found in Brazil make it one of the most widely available and affordable birthstones on this list. One care note: keep it out of prolonged direct sun, since amethyst's color can fade.

March: Aquamarine and Bloodstone

March carries two modern stones: aquamarine as primary, bloodstone as its official alternate. Aquamarine is a pale sea-blue beryl (Mohs 7.5–8, the same mineral family as emerald) traditionally linked to courage, calm, and clear communication — sailors once carried it for safe passage. Bloodstone is a deep green chalcedony flecked with red iron oxide, long associated with strength and grounding rather than aquamarine's calm. Want March's serene half, or its grounded half? Either is a correct answer, and bloodstone is usually the more affordable of the two.

April: Diamond

April's modern birthstone is diamond — pure carbon, Mohs 10, the hardest natural material on Earth. Tradition frames it as a symbol of clarity, strength, and enduring love, part of why it became the default engagement stone. Diamond isn't a stone you'll typically find in a crystal shop's case; if you want April's clarity without precious-gem pricing, clear quartz shares that colorless brilliance and carries its own clarifying associations in crystal tradition. Same visual clarity, at a fraction of the cost.

May: Emerald

May's birthstone is emerald, the rich green beryl colored by trace chromium, Mohs 7.5–8 but more brittle than that hardness suggests because of natural internal inclusions. Tradition ties emerald to renewal, love, and growth — many old sources link it to rebirth and truthful sight. Because of those inclusions, most emeralds are treated with oil or resin to improve clarity, so skip the ultrasonic cleaner and harsh chemicals. If you want emerald's green in a sturdier, more affordable stone, green aventurine or moss agate offer a similar tone.

June: Pearl, Moonstone, and Alexandrite

June is the one month with three official modern stones: pearl, moonstone, and alexandrite. Pearl is organic — grown inside a living mollusk rather than mined — and by far the softest birthstone at Mohs 2.5–3, so it needs gentler handling than anything else on this list. Moonstone (feldspar, Mohs 6–6.5) shares pearl's soft glow with sturdier everyday wear, and alexandrite is prized for shifting color from green in daylight to red under incandescent light. All three carry tradition-framed themes of intuition and new beginnings; for daily-wear jewelry, moonstone or alexandrite holds up better than pearl.

July: Ruby

July's stone is ruby, the red variety of corundum (Mohs 9 — second only to diamond in hardness), colored by trace chromium. Tradition calls it the "king of gems," tied to passion, vitality, and warmth. Because fine ruby sits at precious-gem pricing, garnet or carnelian are honest budget routes to July's warm-red palette — neither is a substitute for ruby's mineral identity, but both carry similar tradition-framed themes of vitality and courage at crystal-shop prices.

August: Peridot, Spinel, and Sardonyx

August carries three modern stones: peridot as primary, spinel and sardonyx as alternates. Peridot is olive-green olivine (Mohs 6.5–7), one of the few gems that forms in essentially a single color rather than a family of shades. Tradition ties it to lightness, well-being, and good cheer — ancient Egyptians reportedly mined it on a Red Sea island and called it the "gem of the sun." Spinel is the more durable of the three (Mohs 8) and comes in a much wider color range, making it the better pick if you want August's stone in a piece you'll wear daily.

September: Sapphire

September's birthstone is sapphire — like ruby, a variety of corundum (Mohs 9), but in every color except red, with deep blue the most recognized. Tradition links sapphire to wisdom, truth, and faithful focus. It shares ruby's exceptional durability, part of why sapphire is one of the safer birthstones for a ring worn every day without a protective setting. There's no modern alternate for September — sapphire stands alone on the list, the way garnet, amethyst, diamond, ruby, and emerald do for their own months.

October: Opal and Tourmaline

October pairs opal as primary with tourmaline as its modern alternate. Opal is hydrated silica (Mohs 5.5–6.5) prized for its play-of-color, a rainbow shimmer caused by light diffracting through microscopic silica spheres, and tradition frames it around creativity, imagination, and emotional honesty. It's also one of the more delicate birthstones — opal can dry out and develop fine internal cracks (crazing) in very dry heat, so it's not the best choice for a ring you'll never take off. Tourmaline is markedly tougher and comes in nearly every color, making it the sturdier option if durability matters more to you than opal's shimmer.

November: Topaz and Citrine

November belongs to topaz, primarily the golden-amber variety (Mohs 8), with citrine as its modern alternate. Tradition ties both to warmth, confidence, and good fortune. Citrine was added to the list specifically as a more affordable, widely available stand-in for imperial topaz, and that's still the honest way to think about it today: citrine is quartz, plentiful and inexpensive, while fine golden topaz commands real-gem pricing. If November is your month and budget matters, citrine gets you the same golden-amber tradition for less.

December: Turquoise, Tanzanite, Zircon, and Blue Topaz

December is the most crowded month on the modern list, with turquoise as primary and tanzanite, zircon, and blue topaz as alternates. Turquoise is an opaque sky-blue phosphate mineral, one of the oldest mined gems in human history, traditionally carried for protection, wisdom, and good fortune. It's also porous and sensitive to oils and chemicals, so it needs more careful handling than most stones on this list. Tanzanite, discovered in Tanzania in 1967 and added to the birthstone list in 2002, gives December a deeper violet-blue option that's considerably more durable for daily wear.

Where birthstones come from: four systems, one calendar

The birthstone list most people know is barely older than a century. In August 1912, the National Association of Jewelers — now Jewelers of America — met in Kansas City and formally standardized a birthstone for each month, drawing on a 1907 retail list compiled by Tiffany & Co.'s chief gemologist, George Frederick Kunz. The goal was explicitly commercial: give jewelers and customers one clear, marketable answer instead of a tangle of regional folk traditions.

That list hasn't stayed frozen. In 1952 the trade added alexandrite to June, citrine to November, and shifted March's primary stone from bloodstone to aquamarine. In 2002 the American Gem Trade Association added tanzanite to December, promoting a gem discovered in Tanzania just decades earlier. Spinel joined August in 2016. Each addition followed the same logic as 1912 — durable, available, marketable stones layered onto the original list rather than replacing it, which is why several months now carry more than one modern option.

Before 1912, there was no single traditional list — just overlapping regional customs across Europe and the Middle East, tracing back by most accounts to the twelve gemstones on the biblical breastplate of Aaron. Wearing a single birthstone tied to your own birth month wasn't even common practice until the eighteenth century; before that, the custom in parts of Europe was to own all twelve stones and wear whichever matched the current month.

Two other systems run in parallel, built on older and more spiritual reasoning than trade history. The mystical system traces to Tibetan astrology, choosing stones for their meditative and energetic associations rather than availability. The Ayurvedic system, rooted in Vedic astrology (Jyotish), goes further still — it links gems to the nine planets and prescribes a stone based on an individual's birth chart rather than birth month alone, traditionally under the guidance of someone trained to read that chart.

These four systems don't always agree, and that's worth saying plainly rather than smoothing over. December is the clearest example: the modern list gives it four options, the mystical system points to onyx, and the Ayurvedic system points to ruby instead. When someone asks what their birthstone is, jewelers — and we — default to the modern list, because it's the one nearly everyone means. The older systems aren't wrong; they're answering a different question.

How to choose

There are at least three reasonable ways to pick a stone, and none is more "correct" than the others.

Birth month is the most common starting point — simple, and what most birthstone jewelry (rings, pendants, family "mother's rings") is built around.

Zodiac sign is a related but different system: your sun sign is tied to a date range, not a calendar month, and those ranges straddle two months at a time. A zodiac stone and a birthstone often overlap but aren't identical — see our zodiac hub for sign-by-sign stones.

The third way is simpler than either: choose whatever stone you're actually drawn to. Birthstones are lore and identity, not a rulebook. If your October birthstone is opal but you've always reached for garnet, no tradition says you can't wear it.

Frequently asked questions

What is my birthstone? Find your birth month in the chart above and match it to the modern stone listed. Most months have one modern birthstone; a handful — March, June, August, October, November, and December — have more than one, and any of them is a valid choice for that month.

Can a month have more than one birthstone? Yes. Six months on the modern list carry more than one official option. This happened across several revisions to the original 1912 list, as jewelers added more accessible or newly discovered stones alongside the originals rather than replacing them outright.

Are birthstones the same as zodiac stones? Not quite. A birthstone is tied to your calendar month; a zodiac stone is tied to your sun sign, and sign date ranges straddle two calendar months. The two systems often land on the same stone for part of a month, but they're built on different logic — see our zodiac hub for sign-specific stones.

Do I have to buy the expensive version of my birthstone? No. Several birthstones are precious gems — diamond, emerald, ruby, sapphire — that carry real-gem pricing, but most months have an affordable, honest alternate: citrine for topaz, garnet or carnelian for ruby, clear quartz for diamond. We note the accessible option in each month's entry above.

How should I care for my birthstone? It depends on the stone. Hard, stable stones like sapphire, ruby, and diamond clean easily with mild soap and water; softer or more porous stones like pearl, opal, and turquoise need gentler handling and should be kept away from perfume, lotion, and prolonged direct sun. Each month's entry above notes the stone's hardness as a rough guide.

Why do the four birthstone systems disagree? Because they were built for different purposes, in different centuries, by different cultures. The modern list is a 1912 commercial standard designed around durability and marketability; the traditional, mystical, and Ayurvedic systems predate it and were built around folklore, meditation practice, and planetary astrology rather than retail. None of them is wrong — they're answering slightly different questions about the same twelve months.

Crystals carry centuries of spiritual tradition. What we share here is what those traditions teach — not medical, mental health, or financial advice. If you're navigating a health concern, please work with a qualified practitioner.