Nolzeite is a rare sodium manganese hydroxide, typically colorless to pale green. It is a late-stage mineral likely formed under alkaline conditions in vugs in altered sodalite syenite. It was first described from Poudrette quarry, La Vallée-du-Richelieu, Montérégie, Québec, Canada.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Nolzeite

Hardness: 4
Luster: Vitreous
Streak: White
Transparency: Transparent

No image

Is this nolzeite?

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 nolzeite with a known reference. Nolzeite sits at Mohs 4, 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.
4
Match the color range
Compare against the expected color range: colorless, pale green.
5
Look at form & habit
Crystal system: triclinic. Typical habit: tabular crystals.

Often confused with

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

Often found alongside nolzeite

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

All properties

Chemical formula: Na(Mn,☐)₂[Si₃(B,Si)O₉(OH)₂](H₂O)₂
Mohs hardness: 4
Density: 2.79 g/cm³
Colors: Colorless Pale green
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Triclinic
Crystal habit: Tabular crystals
Rarity: Rare
Uses: Collector
Host rock: A late-stage mineral likely formed underalkaline conditions in vugs in altered sodalite syenite

Where rockhounds find nolzeite

Classic worldwide localities

Poudrette quarry, La Vallée-du-Richelieu, Montérégie (formerly Rouville County), Québec, Canada

Field-hunting tip

Where it forms: A late-stage mineral likely formed underalkaline conditions in vugs in altered sodalite syenite. If you start seeing aegirine, nepheline, sodalite in float, you are in the right ground. Typical habit: tabular crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify nolzeite?+

Mohs hardness is 4. Luster: vitreous. The streak is white. Common colors include colorless, pale green.

Where is nolzeite found?+

Notable localities include Poudrette quarry, La Vallée-du-Richelieu, Montérégie (formerly Rouville County), Québec, Canada.

What rocks look like nolzeite?+

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

What minerals are found with nolzeite?+

Nolzeite commonly co-occurs with Aegirine, Nepheline, Sodalite, Eudialyte-group minerals, Analcime, Natron. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does nolzeite form in?+

Where it forms: A late-stage mineral likely formed underalkaline conditions in vugs in altered sodalite syenite. Working float back to the host body is the standard way to chase a fresh occurrence.

What is nolzeite used for?+

Nolzeite is used in collector.

Find nolzeite on the map

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