Ilmajokite-(Ce) is a rare hydrated sodium-cerium-titanium silicate belonging to the eudialyte group. It occurs as microscopic, yellowish-brown anhedral grains found within alkaline pegmatite environments in Finland.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareEudialyte Group family

Ilmajokite-(Ce)

Hardness: 1
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this ilmajokite-(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 ilmajokite-(ce) with a known reference. Ilmajokite-(Ce) sits at Mohs 1, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Ilmajokite-(Ce) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Ilmajokite-(Ce) typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: anhedral grains.

Often confused with

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

mineral

Eudialyte

Mohs 5-6

How to tell apart: Eudialyte is the harder of the two (Mohs 5-6 vs. 1).

Compare →

Often found alongside ilmajokite-(ce)

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

All properties

Chemical formula: (Na,Ce,Ba)₄(Ti,Nb)Si₄O₁₃(OH,F)₂·nH₂O
Mohs hardness: 1
Density: 2.2 g/cm³
Colors: Yellow Brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Anhedral Grains
Cleavage: Perfect On Rhombic Prism and Pinacoid
Rarity: Rare
Uses: Collector
Host rock: Alkaline Pegmatites

Where rockhounds find ilmajokite-(ce)

Classic worldwide localities

Mt. Karnsurt, Lovozero massif, Kola Peninsula, Russia

Field-hunting tip

Look in alkaline pegmatites country, the host setting where ilmajokite-(ce) typically forms. If you start seeing arfvedsonite, albite, aegirine in float, you are in the right ground. Field specimens usually show a anhedral grains habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ilmajokite-(ce)?+

Mohs hardness is 1. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown.

Where is ilmajokite-(ce) found?+

Notable localities include Mt. Karnsurt, Lovozero massif, Kola Peninsula, Russia.

Is ilmajokite-(ce) safe to handle?+

This mineral is radioactive. Contains minor thorium; store away from other specimens and wash hands after handling. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like ilmajokite-(ce)?+

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

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

Ilmajokite-(Ce) commonly co-occurs with Arfvedsonite, Albite, Aegirine, Nepheline. Spotting any of these in float or country rock is a useful trip signal.

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

Ilmajokite-(Ce) typically forms in alkaline pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ilmajokite-(ce) used for?+

Ilmajokite-(Ce) is used in collector.

Find ilmajokite-(ce) on the map

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