Quick Answer
May's birthstone is emerald — green beryl colored by chromium and vanadium, rated Mohs 7.5 to 8. It became the modern May stone on the 1912 birthstone list and has long symbolized rebirth, renewal, and love. Nearly all natural emeralds are treated with oil or resin to fill surface fissures; lab-created emerald is a true chemical match, not a simulant like moissanite or cubic zirconia.
What Is May's Birthstone, Emerald?
Emerald is a vivid green variety of beryl, colored by trace chromium and sometimes vanadium. It measures Mohs 7.5 to 8, but nearly every emerald has visible inclusions, nicknamed "jardin" (French for garden), since flawless emeralds are rare. Most emeralds sold today are also treated with oil or resin to make those inclusions less visible.
- Composition: beryl (a silicate mineral), colored green by trace chromium and/or vanadium
- Hardness: Mohs 7.5–8 — durable for regular wear, though softer than moissanite
- Clarity: most emeralds show visible inclusions ("jardin"); eye-clean stones are the exception, not the rule
- Main sources: Colombia, Zambia, Brazil, and Zimbabwe
One thing worth knowing before you buy: the vast majority of natural emerald on the market is treated with oil or a resin filler to make its natural fissures less visible. That treatment is routine and considered standard practice in the trade — reputable sellers disclose it rather than hide it, and it's worth asking about if a listing doesn't say either way. Lab-created emerald, grown with the same chemical structure as a mined stone, is a true synthetic rather than a simulant, and tends to have fewer visible inclusions since growers control clarity.
What Does the Emerald Birthstone Mean?
Emerald has symbolized rebirth, renewal, and love since antiquity, and it became May's official birthstone when US jewelers standardized the modern birthstone list in 1912. Ancient Egyptians mined emerald along the Red Sea as early as 330 BCE, and Cleopatra was famously fond of the stone, associating it with fertility and the arrival of spring.
Today, Colombia produces some of the world's most prized emeralds, valued for their intense green color, and the gem remains a traditional gift for 20th and 35th wedding anniversaries. The name traces back through Old French and Latin to the Greek "smaragdos," which simply means "green stone."
How Do You Care for Emerald Jewelry?
Most emerald is filled with oil or resin, so avoid ultrasonic and steam cleaners, which can drive out the filler and leave inclusions more visible. Clean it instead with warm water, mild soap, and a soft brush, then pat dry. At Mohs 7.5–8, emerald is softer than moissanite, so store it apart from harder stones.
- Take emerald jewelry off before swimming, showering, or cleaning with household chemicals
- Skip ultrasonic and steam cleaners — the vibration and heat can affect oil or resin fillers
- Store pieces separately in a soft pouch or lined box, not loose in a drawer with harder stones
- These are the same everyday habits we recommend for our own sterling silver and moissanite pieces — see our sterling silver and moissanite care guide for more
How to Wear a May Birthday Look in Sterling Silver and Moissanite
We don't currently stock emerald in our catalog, so we style May birthdays with near-colorless moissanite set in 925 sterling silver instead — a bright, budget-friendly look, not a birthstone substitute. A dainty pendant on an adjustable chain layers naturally with other necklaces and doubles as an everyday base layer.
- Keep a birthday pendant short and close to the neck as a "base layer," then add one or two longer chains around it
- An initial or nameplate pendant makes the gift feel personal — a small way to mark the month without needing an actual emerald
- A heart pendant works well as a gift for a mom, sister, or partner with a May birthday
- If you want a real emerald accent, the custom route below is the honest way to add it
Here are a few everyday pieces from our current necklace lineup that work well for this kind of personal, giftable look:
Browse the full lineup in our necklaces collection, or see more budget-friendly gift ideas in our moissanite gifts under $100 guide.
Want an Actual Emerald Piece? We Can Make One
If you want a genuine emerald piece — a birthstone pendant with an emerald accent, a personalized initial charm, or a memorial design — we take custom requests. Share your idea through our custom design inquiry page, and we'll work with you on stone, setting, and sterling silver details before anything is made.
This is where the personal side of a birthstone gift comes in. A May birthday piece doesn't have to be a plain solitaire — a small emerald accent set beside an initial, a number, or a hand-picked design carries more meaning than a stock item. If you're curious how other months in this series are covered, we've also written guides for April's diamond and March's aquamarine and bloodstone.
Frequently Asked Questions
Is emerald a good stone for everyday wear?
It depends on the setting and how it's worn. At Mohs 7.5–8, emerald is reasonably durable, but its natural inclusions make it more prone to chipping from hard knocks than moissanite or diamond. A protective setting, like a bezel, and taking it off for sports or heavy chores helps it hold up well for daily wear.
Does MYNSU sell emerald jewelry?
Not in our standard catalog — we currently stock moissanite and 925 sterling silver pieces, some with pavé cubic zirconia accents. If emerald is specifically what you're after, our custom design process can build a one-off piece around it; reach out through our custom design inquiry page to start that conversation.
Why do so many emeralds get an oil or resin treatment?
Nearly all emeralds form with visible internal fissures, and oiling or resin-filling those fissures makes the stone look clearer and protects it from further damage. It's an old, widely accepted practice in the gem trade — the only issue is when a seller doesn't disclose it, since filled stones need gentler care than untreated ones.
Is lab-created emerald a real emerald?
Yes. Lab-created emerald has the same chemical structure, crystal form, and optical properties as mined emerald — it's grown in a lab rather than found underground, and it isn't a simulant like moissanite or cubic zirconia. It typically costs less than mined emerald and tends to have fewer visible inclusions.
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