Which zodiac should wear moonstone

What a moonstone is doing

Before the signs, the stone. Moonstone is a feldspar, and the thing it is known for is not a color. Inside the stone are very thin alternating layers of two feldspars, and light entering the dome scatters between those layers and comes back out as a blue-white sheen that appears to float a millimeter or two beneath the surface. The effect has a name, adularescence, and the useful thing about it is that it moves. Tilt the stone about five degrees and the blue crosses it and settles somewhere else.

This is why a moonstone photographs badly and looks better in person. A single frame catches one angle, and the stone is not one angle. It is also why the setting matters: polished silver throws its own highlights and competes with the stone for the same light, so the silver around a moonstone is better left matte.

Two practical notes while we are here. Direct sun is the worst light for it, because the sheen gets overwhelmed and the stone reads as a plain pale pebble. And a stone with no internal texture at all, a perfectly clear one with a fixed glow sitting in the middle, is usually glass rather than moonstone. The absence of the word glass on a label is not evidence of anything.

The ruby problem

Here is the awkward part. Cancer is the one sign the Moon rules, and moonstone is named for the Moon, so the pairing should be simple. It is not, because there are two different systems handing out stones and they use different rules.

The modern birthstone list, fixed in 1912, runs by calendar month. Cancer runs from June 21 to July 22, which straddles two months, so a Cancer born in June gets moonstone and a Cancer born in July gets ruby. Same sign, same ruling planet, two entirely different stones, and the only thing that decided it was which side of June 30 they were born on.

I do not work with ruby, and this is not a page trying to talk anyone out of it. If a July Cancer wants the stone the calendar actually assigns them, they should have it. But it is worth being clear about what the calendar is: a commercial standard agreed by jewelers about a century ago, useful because everyone uses it, and not older than the association between the Moon and this stone. Roman writers were already calling it a moon stone. Indian tradition arrived at the same reading independently. The argument predates the list by centuries.

So if you are a Cancer born in July and the ruby does not feel like yours, that is not you ignoring tradition. It is you preferring the older of two traditions.

So who should wear it?

Water. Cancer is the stone's home address. Scorpio wears it as the deep end of the same water, a stone that gives nothing away at the surface and does everything underneath. Pisces wears it as water without a shore, which suits a stone whose light has no edge you can point to.

Air. Gemini has the paper claim: twenty of June's thirty days are Gemini, so most people with a calendar right to June's stone are this sign. Libra is ruled by Venus and is allowed to choose a stone because of how it looks, which is a complete reason and one this page is happy to accept. Aquarius comes at it a third way, and that page is not written yet.

Fire. Aries, Leo and Sagittarius are the harder sell, and I am not going to pretend otherwise. Fire signs are usually pointed at stones that assert themselves, and moonstone does the opposite. That said, a stone that only shows itself when it moves is not a bad counterweight for someone who is always moving.

Earth. Taurus, Virgo and Capricorn tend to want a stone that lasts, and here the honest answer is a caution rather than a pitch. Moonstone sits at 6 to 6.5 on the Mohs scale, below quartz at 7, and ordinary dust contains quartz. It will hold its polish for years with a little care, but it is not the stone to hand someone who never takes jewelry off.

Which wrist, and how to wear it

There is a tradition that says the left, because the left is the receiving side. There is no evidence behind it and I am not going to dress it up as anything more than a custom, but customs are allowed to be reasons.

The practical case is different and points the other way for most people: the hand you write with takes more knocks, so a bracelet on the non-dominant wrist keeps its surface longer. Beyond that, wear it against skin or a plain cuff rather than over a knit sleeve, and keep it off the same shelf as anything faceted.

If you want the version of this with your own sign's constellation on the coin, the twelve signs are here.