Rainbow Moonstone is technically a variety of Labradorite feldspar that exhibits a characteristic adularescence, or schiller, displaying flashes of blue and multi-colored light. It is commonly found in India and Sri Lanka, often fashioned into cabochons to best display its optical play-of-color. Collectors should look for high translucency and strong blue spectral flashes when evaluating specimens.

Hardness

6-6.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

gemstonecommonOrthoclase family

Rainbow Moonstone

Also: White Labradorite

Hardness: 6-6.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this rainbow moonstone?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch rainbow moonstone with a known reference. Rainbow Moonstone sits at Mohs 6-6.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Rainbow Moonstone leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Rainbow Moonstone typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: white, colorless, blue, rainbow.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals.

Often confused with

Rainbow Moonstone vs. its common look-alikes, and how to tell them apart in the field.

How to tell apart: Luster reads vitreous on Rainbow Moonstone and waxy on Chalcedony.

Often found alongside rainbow moonstone

Minerals reported to co-occur with rainbow moonstone. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: KAlSi₃O₈
Mohs hardness: 6-6.5
Density: 2.56-2.63 g/cm³
Colors: White Colorless Blue Rainbow
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals
Cleavage: Perfect in Two Directions
Rarity: Common
Uses: Gemstone, Lapidary, Collector
Host rock: Pegmatites
Typical price: $10-100 per carat for gem-grade material

Where rockhounds find rainbow moonstone

Classic worldwide localities

India
Sri Lanka
Madagascar
Australia

Field-hunting tip

Look in pegmatites country, the host setting where rainbow moonstone typically forms. If you start seeing quartz, muscovite, biotite in float, you are in the right ground. Field specimens usually show a tabular crystals habit, so train your eye for that shape before scanning the outcrop.

More rainbow moonstone photos

Common questions

How do you identify rainbow moonstone?+

Mohs hardness is 6-6.5. It typically shows a vitreous luster. The streak is white. Common colors include white, colorless, blue, rainbow.

Where is rainbow moonstone found?+

Notable localities include India; Sri Lanka; Madagascar; Australia.

How much is rainbow moonstone worth?+

Typical asking prices fall in the range of $10-100 per carat for gem-grade material. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like rainbow moonstone?+

Rainbow Moonstone is most often confused with Opal, Chalcedony, Albite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with rainbow moonstone?+

Rainbow Moonstone commonly co-occurs with Quartz, Muscovite, Biotite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does rainbow moonstone form in?+

Rainbow Moonstone typically forms in pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is rainbow moonstone used for?+

Rainbow Moonstone is used in gemstone, lapidary, collector.

Find rainbow moonstone on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.