Lahnsteinite is a rare secondary zinc sulfate mineral typically found as delicate, pearly-white coatings or small platy crystals in oxidized mine environments. It is named after its type locality in Lahnstein, Germany, and is highly sought after by collectors of micro-minerals and rare species.

Hardness

Mohs

Luster

Pearly

Streak

White

Transparency

Translucent

mineralrare

Lahnsteinite

Hardness: 2
Luster: Pearly
Streak: White
Transparency: Translucent

No image

Is this lahnsteinite?

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

Often confused with

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

mineral

Gordaite

Mohs 2

How to tell apart: Luster reads pearly on Lahnsteinite and vitreous to pearly on Gordaite.

How to tell apart: Luster reads pearly on Lahnsteinite and dull on Hydrozincite.

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Often found alongside lahnsteinite

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

All properties

Chemical formula: Zn₄(SO₄)(OH)₆·3H₂O
Mohs hardness: 2
Density: 2.98 g/cm³
Colors: White Colorless
Streak: White
Luster: Pearly
Transparency: Translucent
Crystal system: Triclinic
Crystal habit: Platy Crystals, Crusts
Cleavage: Perfect
Rarity: Rare
Uses: Collector
Host rock: Oxidized Hydrothermal Zinc Deposits

Where rockhounds find lahnsteinite

Classic worldwide localities

Lahnstein, Rhineland-Palatinate, Germany

Field-hunting tip

Look in oxidized hydrothermal zinc deposits country, the host setting where lahnsteinite typically forms. If you start seeing smithsonite, hemimorphite, sphalerite in float, you are in the right ground. Field specimens usually show a platy crystals, crusts habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify lahnsteinite?+

Mohs hardness is 2. It typically shows a pearly luster. The streak is white. Common colors include white, colorless.

Where is lahnsteinite found?+

Notable localities include Lahnstein, Rhineland-Palatinate, Germany.

Is lahnsteinite safe to handle?+

It contains toxic constituents. Contains zinc, which can be toxic if ingested or inhaled as dust. Wash hands thoroughly after handling specimens. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like lahnsteinite?+

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

What minerals are found with lahnsteinite?+

Lahnsteinite commonly co-occurs with Smithsonite, Hemimorphite, Sphalerite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does lahnsteinite form in?+

Lahnsteinite typically forms in oxidized hydrothermal zinc deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is lahnsteinite used for?+

Lahnsteinite is used in collector.

Find lahnsteinite on the map

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