Nyerereite is a rare carbonate mineral famous for being a primary constituent of the unique natrocarbonatite lavas of the Oldoinyo Lengai volcano in Tanzania. It typically occurs as small, glassy crystals or granular masses associated with gregoryite. It is extremely sensitive to moisture and will decompose rapidly if exposed to high humidity or water, requiring specialized storage conditions for collectors.
Is this nyerereite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch nyerereite with a known reference. Nyerereite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: colorless.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: platy, pseudo hexagonal, twinning common.
Often confused with
Nyerereite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside nyerereite
Minerals reported to co-occur with nyerereite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂Ca(CO₃)₂
- Mohs hardness
- 3.5
- Density
- 2.541 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Semitransparent
- Crystal system
- Orthorhombic
- Crystal habit
- Platy, pseudo hexagonal, twinning common
- Cleavage
- Poor
- Rarity
- Rare
- Uses
- Collector
- Host rock
- As phenocrysts in carbonate lavas, persistent due to rapid cooling
Where rockhounds find nyerereite
Classic worldwide localities
- Oldoinyo Lengai and Kerimasi volcanos, Tanzania
Field-hunting tip
Where it forms: As phenocrysts in carbonate lavas, persistent due to rapid cooling. If you start seeing halite, sylvite, fluorite in float, you are in the right ground. Typical habit: platy, pseudo hexagonal, twinning common. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify nyerereite?+
Where is nyerereite found?+
What rocks look like nyerereite?+
What minerals are found with nyerereite?+
What kind of rock does nyerereite form in?+
What is nyerereite used for?+
Find nyerereite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
