Chiolite is a rare sodium aluminum fluoride mineral that is structurally related to cryolite. It typically occurs as white or colorless massive aggregates within unique pegmatite environments, most famously associated with the cryolite deposits in Ivigtut, Greenland.

Hardness

3.5-4

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrare

Chiolite

Hardness: 3.5-4
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this chiolite?

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 chiolite with a known reference. Chiolite sits at Mohs 3.5-4 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Chiolite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Chiolite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: white, colorless.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: granular, massive, or rarely as pyramidal crystals.

Often confused with

Chiolite vs. its common look-alikes — and how to tell them apart in the field.

mineral

Cryolite

Mohs 2.5-3

How to tell apart: Luster reads vitreous on Chiolite and vitreous to greasy on Cryolite.

Often found alongside chiolite

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

All properties

Chemical formula: Na₅Al₃F₁₄
Mohs hardness: 3.5-4
Density: 3.0 g/cm³
Colors: White Colorless
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Tetragonal
Crystal habit: Granular, Massive, Or Rarely as Pyramidal Crystals
Cleavage: Poor
Rarity: Rare
Uses: Collector, Geological Study
Host rock: Granite Pegmatites
Typical price: $50-300 per specimen

Where rockhounds find chiolite

Classic worldwide localities

Ivigtut (Greenland)
Ilmen Mountains (Russia)
Pikes Peak (USA)

Field-hunting tip

Look in granite pegmatites country — that is the host setting where chiolite typically forms. If you start seeing cryolite, siderite, galena in float, you are in the right ground. Field specimens usually show a granular, massive, or rarely as pyramidal crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify chiolite?+

Mohs hardness is 3.5-4. It typically shows a vitreous luster. The streak is white. Common colors include white, colorless.

Where is chiolite found?+

Notable localities include Ivigtut (Greenland); Ilmen Mountains (Russia); Pikes Peak (USA).

How much is chiolite worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like chiolite?+

Chiolite is most often confused with Cryolite, Prosopite, Fluorite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with chiolite?+

Chiolite commonly co-occurs with Cryolite, Siderite, Galena, Sphalerite, Fluorite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does chiolite form in?+

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

What is chiolite used for?+

Chiolite is used in collector, geological study.

Find chiolite on the map

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