Ferri-mottanaite-(Ce) is a rare boron-bearing sorosilicate mineral belonging to the allanite group. It is primarily found in metamorphic environments and is identified by its distinct chemical composition featuring iron and cerium, usually occurring as small, brownish, prismatic crystals.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareAllanite Group family

Ferri-mottanaite-(Ce)

Hardness: 6
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this ferri-mottanaite-(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 ferri-mottanaite-(ce) with a known reference. Ferri-mottanaite-(Ce) 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. Ferri-mottanaite-(Ce) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Ferri-mottanaite-(Ce) typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, reddish-brown.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: prismatic crystals.

Often confused with

Ferri-mottanaite-(Ce) vs. its common look-alikes — and how to tell them apart in the field.

mineral

Allanite

Mohs 5.5-6

How to tell apart: Streak differs — Ferri-mottanaite-(Ce) leaves white, Allanite leaves gray; luster reads vitreous on Ferri-mottanaite-(Ce) and submetallic on Allanite.

Often found alongside ferri-mottanaite-(ce)

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

All properties

Chemical formula: CaCe₄Fe³⁺(Si₂B)O₁₂F(OH)₂
Mohs hardness: 6
Density: 3.8-4.0 g/cm³
Colors: Yellow Brown Reddish-brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Prismatic Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Metamorphic Rocks
Typical price: $50-300 per specimen

Where rockhounds find ferri-mottanaite-(ce)

Classic worldwide localities

Malenco Valley, Italy
Gravelotte, South Africa

Field-hunting tip

Look in metamorphic rocks country — that is the host setting where ferri-mottanaite-(ce) typically forms. If you start seeing quartz, albite, titanite in float, you are in the right ground. Field specimens usually show a prismatic crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ferri-mottanaite-(ce)?+

Mohs hardness is 6. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown, reddish-brown.

Where is ferri-mottanaite-(ce) found?+

Notable localities include Malenco Valley, Italy; Gravelotte, South Africa.

How much is ferri-mottanaite-(ce) 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 ferri-mottanaite-(ce)?+

Ferri-mottanaite-(Ce) is most often confused with Allanite, Mottanaite-(Ce), Epidote. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with ferri-mottanaite-(ce)?+

Ferri-mottanaite-(Ce) commonly co-occurs with Quartz, Albite, Titanite, Garnet. Spotting any of these in float or country rock is a useful trip signal.

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

Ferri-mottanaite-(Ce) typically forms in metamorphic rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ferri-mottanaite-(ce) used for?+

Ferri-mottanaite-(Ce) is used in collector.

Find ferri-mottanaite-(ce) on the map

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