Griceite is a rare lithium fluoride mineral that typically forms as colorless or white cubic crystals. It was first discovered in the highly diverse alkaline pegmatites of Mont Saint-Hilaire and is highly sought after by advanced collectors for its rarity and simple chemical composition.

Hardness

~4.5

Mohs

Luster

Vitreous or porcelaneous to waxy or dull

Streak

White

Transparency

Translucent, quickly becoming opaque on exposure

mineralrare

Griceite

Hardness: ~4.5
Luster: Vitreous or porcelaneous to waxy or dull
Streak: White
Transparency: Translucent, quickly becoming opaque on exposure

Is this griceite?

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 griceite with a known reference. Griceite sits at Mohs ~4.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous or porcelaneous to waxy or dull.
4
Match the color range
Compare against the expected color range: green white, yellowish white, white.
5
Look at form & habit
Crystal system: cubic. Typical habit: inclusions, microscopic crystals.

Often confused with

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

mineral

Halite

Mohs 2-2.5

How to tell apart: Griceite is noticeably harder (Mohs ~4.5 vs. 2-2.5).

How to tell apart: Griceite is noticeably harder (Mohs ~4.5 vs. 2).

Compare →

Often found alongside griceite

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

All properties

Chemical formula: LiF
Mohs hardness: ~4.5
Density: 2.62 g/cm³
Colors: Green whiteYellowish white White
Streak: White
Luster: Vitreous or porcelaneous to waxy or dull
Transparency: Translucent, quickly becoming opaque on exposure
Crystal system: Cubic
Crystal habit: Inclusions, microscopic crystals
Cleavage: {100}, good
Fluorescence: Light yellow under SW UV
Rarity: Rare
Uses: Collector
Host rock: In sodalite inclusions in hornfels associated with an intrusive alkalic gabbro-syenite complex

Where rockhounds find griceite

Classic worldwide localities

Mont Saint-Hilaire, Quebec, Canada

Field-hunting tip

Where it forms: In sodalite inclusions in hornfels associated with an intrusive alkalic gabbro-syenite complex. If you start seeing sodalite, ussingite, villiaumite in float, you are in the right ground. Typical habit: inclusions, microscopic crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify griceite?+

Mohs hardness is ~4.5. Luster: vitreous or porcelaneous to waxy or dull. The streak is white. Common colors include green white, yellowish white, white.

Where is griceite found?+

Notable localities include Mont Saint-Hilaire, Quebec, Canada.

What rocks look like griceite?+

Griceite is most often confused with Halite, Sylvite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with griceite?+

Griceite commonly co-occurs with Sodalite, Ussingite, Villiaumite, Eudialyte, Sphalerite, Serandite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does griceite form in?+

Where it forms: In sodalite inclusions in hornfels associated with an intrusive alkalic gabbro-syenite complex. Working float back to the host body is the standard way to chase a fresh occurrence.

What is griceite used for?+

Griceite is used in collector.

Find griceite on the map

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