Retzian-(Ce) is a rare arsenate mineral occurring primarily in metamorphosed manganese deposits. It is typically found as small, reddish-brown tabular crystals often associated with hausmannite and carbonate minerals in Swedish localities.

Hardness

Mohs

Luster

Vitreous to greasy

Streak

Pale brown

Transparency

Subtranslucent

mineralrareRetzian Group family

Retzian-(Ce)

Hardness: 4
Luster: Vitreous to greasy
Streak: Pale brown
Transparency: Subtranslucent

Is this retzian-(ce)?

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 retzian-(ce) with a known reference. Retzian-(Ce) sits at Mohs 4, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: pale brown.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous to greasy.
4
Match the color range
Compare against the expected color range: dark brown, chestnut brown.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: tabular crystals, massive.

Often confused with

Retzian-(Ce) vs. its common look-alikes, and how to tell them apart in the field.

How to tell apart: Streak differs, so Retzian-(Ce) leaves pale brown, Retzian-(Nd) leaves very pale brown.

Often found alongside retzian-(ce)

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

All properties

Chemical formula: Mn₂Ce(AsO₄)(OH)₄
Mohs hardness: 4
Density: 4.15 g/cm³
Colors: Dark brownChestnut brown
Streak: Pale brown
Luster: Vitreous to greasy
Transparency: Subtranslucent
Crystal system: Orthorhombic
Crystal habit: Tabular crystals, massive
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: A rare mineral in cavities in porous dolomite

Where rockhounds find retzian-(ce)

Classic worldwide localities

Moss mine, near Nordmark, Värmland, Sweden

Field-hunting tip

Where it forms: A rare mineral in cavities in porous dolomite. If you start seeing jacobsite, pyrochroite in float, you are in the right ground. Typical habit: tabular crystals, massive. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify retzian-(ce)?+

Mohs hardness is 4. Luster: vitreous to greasy. The streak is pale brown. Common colors include dark brown, chestnut brown.

Where is retzian-(ce) found?+

Notable localities include Moss mine, near Nordmark, Värmland, Sweden.

Is retzian-(ce) safe to handle?+

Retzian-(Ce) contains arsenic and calls for real care. Contains arsenic, which is toxic if ingested or inhaled. Handle with care, wash hands after handling, and avoid creating dust when breaking specimens.

What rocks look like retzian-(ce)?+

Retzian-(Ce) is most often confused with Retzian-(Nd), Retzian-(La). A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with retzian-(ce)?+

Retzian-(Ce) commonly co-occurs with Jacobsite, Pyrochroite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does retzian-(ce) form in?+

Where it forms: A rare mineral in cavities in porous dolomite. Working float back to the host body is the standard way to chase a fresh occurrence.

What is retzian-(ce) used for?+

Retzian-(Ce) is used in collector.

Find retzian-(ce) on the map

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