Moonstone's meaning starts with its glow. The soft, milky light that seems to float just under its surface has tied it to the Moon for centuries, and in crystal practice it's associated with intuition, cycles and new beginnings. The stone is a feldspar, and one of June's three birthstones. The glow is real physics and the moon lore around it is genuinely old, which makes moonstone one of the few crystals whose traditional meaning and physical character point the same way.
The glow has a name: adularescence
Moonstone is mostly orthoclase, a potassium feldspar, with sodium-rich albite mixed through it. As the stone forms and cools, the two separate into alternating layers about half a micron thick, close to the wavelength of visible light. Light entering the stone scatters off those layers and comes back as a billowing sheen gemologists call adularescence. Thinner layers give the prized electric blue; thicker ones a whiter, softer glow.
Look closely at a moonstone and you may see tiny tension cracks that gemologists nickname "centipedes." They're a normal sign of a natural stone. Some pieces also show a thin cat's-eye line across the dome, and a very few show a star.
Moonstone also comes in more body colors than people expect: colorless and white, but also gray, peach, green and brown, each carrying its own sheen. Gemologists prize stones that are nearly transparent with a lively blue glow centered on the dome, which is why moonstone is almost always cut as a smooth cabochon rather than faceted. Cloudier white and peach stones cost far less and are perfectly good for a pocket or an altar.
Most commercial moonstone today comes from Sri Lanka, with other deposits in India, Madagascar, Myanmar and elsewhere. Historically the most valuable transparent stones with a strong blue sheen came from Myanmar.
Moonbeams, Art Nouveau and Florida
Few stones have a longer link with the Moon. In Hindu mythology, moonstone is made of solidified moonbeams. The Romans, too, believed it came from the Moon's rays, and both Greeks and Romans associated it with their lunar deities. Legends also credited it with bringing good luck, and one held that a moonstone held in the mouth at the full moon would let you see the future.
The stone's older gem name, adularia, comes from Mount Adular in Switzerland, in the St Gotthard area, an early source of fine moonstone. Many centuries later, Art Nouveau designers including René Lalique and Louis Comfort Tiffany set moonstones in their jewelry, and the gem came back again with the 1960s "flower child" look.
Then there's Florida. In 1970 the state named moonstone its official gemstone to honor the Moon landings launched from Kennedy Space Center, even though moonstone doesn't occur naturally there. It's a state gem chosen for the sky rather than the ground.
June's birthstone and the Moon's sign
Moonstone has been a June birthstone since the American list of 1912, sharing the month with pearl and, since the 1950s, alexandrite. Our guide to birthstones by month has the full calendar.
In astrology, the Moon rules Cancer, so moonstone is the classic Cancer stone, and Cancers born in late June get it twice over. You don't need a Cancer Sun to use it, though. The Moon in your own chart describes emotional needs and what comfort looks like for you; if you'd like a stone that speaks to that part of you, find your Moon sign with the Moon sign calculator.
In tarot, the card the Golden Dawn system gives to the Moon is The High Priestess, the card of intuition and quiet knowing, which makes an easy pairing for a moonstone on the altar.
A small full moon practice with moonstone
Moonstone fits naturally into lunar rituals. Here's a short one for a full moon night; check upcoming full moon dates for the next one.
- Set the stone on a windowsill where moonlight can reach it, or simply where you can see the sky.
- Write down one thing that has come to fullness this month: a project finished, a feeling finally named, a habit that stuck.
- Write one thing you're ready to let wane over the next two weeks.
- Hold the moonstone while you read both lines aloud, then leave it on the sill overnight.
- In the morning, put it somewhere you'll see it until the new moon, as a reminder of what you're letting go.
For a fuller version with candles and journaling, see our full moon ritual. The practice is about attention and timing, not anything the moonlight does to the stone, and that's what makes it repeatable month after month.
Gentle hands: moonstone care
Moonstone is more delicate than it looks. It's 6 to 6.5 on the Mohs scale, softer than quartz, and it has perfect cleavage, meaning a sharp knock can split it along a flat plane. That's why jewelers usually set it in pendants, earrings and pins rather than rings that take daily bumps.
- Clean it with warm, soapy water and a soft cloth. GIA, the gemological institute, recommends that as the only cleaning method.
- Never use ultrasonic or steam cleaners, and avoid high heat or sudden temperature changes, which can crack it.
- Store it apart from harder stones, which will scratch the polish and dull the glow.
- Keep it out of drinking water, like every crystal.
Questions readers ask
Is rainbow moonstone real moonstone?
Not technically. Rainbow moonstone is a transparent, colorless labradorite, a related feldspar, with a multicolored glow. It's a natural stone and lovely in its own right; our labradorite meaning guide explains its flash.
Can I charge moonstone in moonlight?
Leaving stones out at the full moon is a popular tradition, and moonlight can't harm moonstone. Think of it as a ritual for you rather than a recharge for the stone, and bring it in before it sits in hot midday sun on a windowsill.
Is moonstone good for an engagement ring?
It can be, with care. Choose a protective setting such as a bezel, take the ring off for gardening, the gym and housework, and expect to have it checked by a jeweler now and then. For a ring worn hard every day, a tougher stone may suit you better.
What is the difference between moonstone and selenite?
Both are named for the Moon and both glow softly, but they're very different minerals. Moonstone is a feldspar of moderate hardness; selenite is gypsum, so soft you can scratch it with a fingernail, and it dissolves slowly in water. Our selenite meaning guide covers its care.
