Nullaginite is a rare nickel carbonate that typically forms as bright green, delicate radiating sprays or crusts within weathering ultramafic deposits. It is most commonly found in association with other secondary nickel minerals in Australian localities and requires a hand lens to appreciate its fine acicular crystal structure.
Is this nullaginite?
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 nullaginite with a known reference. Nullaginite sits at Mohs 3 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Nullaginite leaves a pale green streak.
- 3Read the lusterHold the specimen under a strong light. Nullaginite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: bright green, apple green.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: acicular crusts, radiating sprays, micro-crystals.
Often confused with
Nullaginite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside nullaginite
Minerals reported to co-occur with nullaginite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ni₂(CO₃)(OH)₂
- Mohs hardness
- 3
- Density
- 3.37 g/cm³
- Colors
- Streak
- Pale Green
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Acicular Crusts, Radiating Sprays, Micro-crystals
- Cleavage
- Perfect On {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Nickel-rich Ultramafic Rocks and Hydrothermal Weathering Crusts
- Typical price
- $50-300 per thumbnail specimen
Where rockhounds find nullaginite
Classic worldwide localities
- Nullagine, Western Australia
- Widgiemooltha, Western Australia
Field-hunting tip
Look in nickel-rich ultramafic rocks and hydrothermal weathering crusts country — that is the host setting where nullaginite typically forms. If you start seeing magnesite, goethite, quartz in float, you are in the right ground. Field specimens usually show a acicular crusts, radiating sprays, micro-crystals habit, so train your eye for that shape before scanning the outcrop.





