Crystals
Moonstone is orthoclase feldspar, Mohs 6 to 6.5, used for cycles, feeling, new beginnings. The mineralogy, whether it is safe in water and sunlight, what gets substituted for it, and what a stone can honestly do.
Start with the mineralogy, because most of the bad advice about this stone follows from not knowing it. Moonstone is orthoclase feldspar. On colour: The blue sheen is adularescence: light scattering between alternating layers of two feldspars that unmixed as the stone cooled.
Where it comes from: Sri Lanka and southern India for the fine blue material, Madagascar for the rest.
| Property | Value |
|---|---|
| Mineral species | Orthoclase feldspar |
| Chemical formula | KAlSi3O8 |
| Mohs hardness | 6 to 6.5 |
| Crystal system | Monoclinic |
| Chakra | Sacral and Third Eye |
| Usually linked to | Cancer, and to the Moon |
Hardness matters more than it sounds. The Mohs scale runs from talc at 1 to diamond at 10, and anything below about 5.5 can be scratched by ordinary window glass or by the quartz dust in everyday grit. At 6 to 6.5, moonstone is hard enough to handle daily wear without much trouble, though it will still scratch a softer stone it is stored against.
Used for anything cyclical: moods, months, fertility, starting again. It is the stone most consistently handed to people at a beginning, and the one most associated with the Moon in both Indian and Western practice.
In the shorthand most shops and books use, it is a Sacral and Third Eye stone, and the three words attached to it most often are cycles, feeling, new beginnings.
This is the section that matters, and the one most pages get wrong. Cleansing advice is handed around as though every stone were the same mineral, and it is not. Here is what moonstone will actually survive.
| Method | Safe? | Why |
|---|---|---|
| Water | Briefly | Brief contact only. Dry it straight away rather than leaving it to sit wet. |
| Direct sunlight | Yes | Direct sunlight does no damage. |
| Salt or salt water | No | No salt, dry or dissolved. It is abrasive and it attacks softer and porous stones. |
| Moonlight | Yes | Harmless to every stone on this list, which is most of why it is the method that suits everything. |
| Smoke, sound or breath | Yes | Nothing physical touches the stone, so nothing can be damaged by it. |
Much of the cheap white moonstone is a different feldspar with no real sheen, and some of it is opalite, which is manufactured glass. Real moonstone's glow moves across the surface as you tilt it. Opalite's does not.
Two general rules that hold across the whole shop. If the price is far below everything else on the shelf of that size, something has been substituted or treated. And a stone sold with no locality at all is usually one the seller cannot trace, which in this trade often means tumbled, dyed and bagged somewhere a long way from where it came out of the ground.
Moonstone is usually linked to Cancer, and to the Moon. Worth being straight about this: crystal and zodiac pairings are modern, they are not consistent between sources, and two reputable books will give you two different signs for the same stone. They are a useful organising idea rather than a tradition with a single lineage behind it.
If you want the part of this that does have a fixed method behind it, the Sun in Cancer sets out what that sign actually describes, and it is calculated from a date rather than assigned by a writer.
Every piece of moonstone in the shop is the same stone with the same associations, which is both the appeal and the limit of it. A birth chart is the opposite: it is calculated from your date, time and place and it describes one person. If you do not know your birth time, this covers how to find it.
Briefly, and dry it immediately. It is not a stone to leave soaking or to rinse often.
No. Sunlight does not damage it.
Cycles, feeling, new beginnings. It is associated with the Sacral and Third Eye chakra.
Mohs 6 to 6.5. That is hard enough for daily handling.
Much of the cheap white moonstone is a different feldspar with no real sheen, and some of it is opalite, which is manufactured glass.
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