Nickelalumite is a rare secondary mineral found in the oxidation zones of nickel-rich ore deposits. Collectors typically search for its distinct blue to blue-green platy or micaceous crusts, often associated with other secondary copper and nickel species.

Hardness

2.5-3

Mohs

Luster

Pearly

Streak

White

Transparency

Translucent

mineralrareNickelalumite Group family

Nickelalumite

Hardness: 2.5-3
Luster: Pearly
Streak: White
Transparency: Translucent

Is this nickelalumite?

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 nickelalumite with a known reference. Nickelalumite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Nickelalumite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Nickelalumite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: blue, blue-green.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: platy crystals, crusts, micaceous aggregates.

Often confused with

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

How to tell apart: Streak differs, so Nickelalumite leaves white, Zaratite leaves pale green; luster reads pearly on Nickelalumite and vitreous on Zaratite.

Compare →

Often found alongside nickelalumite

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

All properties

Chemical formula: NiAl₄(SO₄)(OH)₁₂·3H₂O
Mohs hardness: 2.5-3
Density: 2.4 g/cm³
Colors: Blue Blue-green
Streak: White
Luster: Pearly
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Platy Crystals, Crusts, Micaceous Aggregates
Cleavage: Perfect
Rarity: Rare
Uses: Collector, Scientific Research
Host rock: Oxidized Nickeliferous Ore Deposits
Typical price: $50-300 per specimen

Where rockhounds find nickelalumite

Classic worldwide localities

Czech Republic
Germany
France

Field-hunting tip

Look in oxidized nickeliferous ore deposits country, the host setting where nickelalumite typically forms. If you start seeing gypsum, goethite, malachite in float, you are in the right ground. Field specimens usually show a platy crystals, crusts, micaceous aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify nickelalumite?+

Mohs hardness is 2.5-3. It typically shows a pearly luster. The streak is white. Common colors include blue, blue-green.

Where is nickelalumite found?+

Notable localities include Czech Republic; Germany; France.

How much is nickelalumite 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 nickelalumite?+

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

What minerals are found with nickelalumite?+

Nickelalumite commonly co-occurs with Gypsum, Goethite, Malachite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does nickelalumite form in?+

Nickelalumite typically forms in oxidized nickeliferous ore deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is nickelalumite used for?+

Nickelalumite is used in collector, scientific research.

Find nickelalumite on the map

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