Rinmanite is an extremely rare zinc antimonate mineral first discovered in the famous Långban mines of Sweden. It typically appears as small, yellowish-black to dark red tabular crystals embedded within manganese-rich metamorphic rocks.

Hardness

Mohs

Luster

Submetallic

Streak

Brown

Transparency

Opaque

mineralrare

Rinmanite

Hardness: ~6
Luster: Submetallic
Streak: Brown
Transparency: Opaque

Is this rinmanite?

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 rinmanite with a known reference. Rinmanite sits at Mohs ~6, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: brown.
3
Read the luster
Hold the specimen under a strong light. Luster: submetallic.
4
Match the color range
Compare against the expected color range: black, very dark red.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: acicular, microscopic crystals.

Often confused with

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

mineral

Berzeliite

Mohs 4.5-5

How to tell apart: Rinmanite is noticeably harder (Mohs ~6 vs. 4.5-5); streak differs, so Rinmanite leaves brown, Berzeliite leaves nearly white to yellow-orange; luster reads submetallic on Rinmanite and resinous on Berzeliite.

Compare →

Often found alongside rinmanite

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

All properties

Chemical formula: ZnSb⁵⁺(Fe³⁺₂Mg)O₇(OH)
Mohs hardness: ~6
Density: 5.13 g/cm³
Colors: BlackVery dark red
Streak: Brown
Luster: Submetallic
Transparency: Opaque
Crystal system: Hexagonal
Crystal habit: Acicular, microscopic crystals
Cleavage: {100}, good
Rarity: Rare
Uses: Collector
Host rock: In veinlets and lenses in dolomitic marble and silicate skarn hosting a pyritiferous Zn-Pb-Fe-Cu-Sb-Ag-deposit

Where rockhounds find rinmanite

Classic worldwide localities

Garpenberg Norra deposit, Hedemora, Dalarna (= Dalecarlia), south-central Sweden

Field-hunting tip

Where it forms: In veinlets and lenses in dolomitic marble and silicate skarn hosting a pyritiferous Zn-Pb-Fe-Cu-Sb-Ag-deposit. If you start seeing tremolite, manganocummingtonite, talc in float, you are in the right ground. Typical habit: acicular, microscopic crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify rinmanite?+

Mohs hardness is ~6. Luster: submetallic. The streak is brown. Common colors include black, very dark red.

Where is rinmanite found?+

Notable localities include Garpenberg Norra deposit, Hedemora, Dalarna (= Dalecarlia), south-central Sweden.

Is rinmanite safe to handle?+

Rinmanite contains antimony. Contains zinc and antimony; wash hands thoroughly after handling and avoid ingestion or inhalation of dust.

What rocks look like rinmanite?+

Rinmanite is most often confused with Berzeliite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with rinmanite?+

Rinmanite commonly co-occurs with Tremolite, Manganocummingtonite, Talc, Franklinite, Baryte, Svabite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does rinmanite form in?+

Where it forms: In veinlets and lenses in dolomitic marble and silicate skarn hosting a pyritiferous Zn-Pb-Fe-Cu-Sb-Ag-deposit. Working float back to the host body is the standard way to chase a fresh occurrence.

What is rinmanite used for?+

Rinmanite is used in collector.

Find rinmanite on the map

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