Eltyubyuite is a rare member of the sodalite group discovered in the Chegem caldera of Russia. It typically forms small, yellow to light brown dodecahedral crystals within calc-silicate xenoliths, requiring microscopic examination for positive identification.

Hardness

5.5-6

Mohs

Transparency

Transparent

mineralrareSodalite Group family

Eltyubyuite

Hardness: 5.5-6
Transparency: Transparent

No image

Is this eltyubyuite?

3-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 eltyubyuite with a known reference. Eltyubyuite sits at Mohs 5.5-6, softer than the next harder reference, harder than the previous one.
2
Match the color range
Compare against the expected color range: yellow.
3
Look at form & habit
Crystal system: cubic. Typical habit: dodecahedral crystals.

Often confused with

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

Often found alongside eltyubyuite

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

All properties

Chemical formula: Ca₆Fe₅Si₂O₁₆Cl₃
Mohs hardness: 5.5-6
Density: 3.349 g/cm³
Colors: Yellow
Transparency: Transparent
Crystal system: Cubic
Crystal habit: Dodecahedral crystals
Rarity: Rare
Uses: Collector
Host rock: From a thermally-altered carbonate-silicate xenolith (20 m long) in ignimbrite that created sanidinite facies metamorphism (Upper Chegem Caldera)

Where rockhounds find eltyubyuite

Classic worldwide localities

Xenolith No.1, the Upper Chegem Caldera, Northern Caucasus, Kabardino-Balkaria and the Kel’ Plateau, Shadil-Khokh volcano, southern flank of the Greater Caucasian Mountain Range, Southern Ossetia, Russia
Eifel, Germany

Field-hunting tip

Where it forms: From a thermally-altered carbonate-silicate xenolith (20 m long) in ignimbrite that created sanidinite facies metamorphism (Upper Chegem Caldera). If you start seeing larnite, rondorfite, wadalite in float, you are in the right ground. Typical habit: dodecahedral crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify eltyubyuite?+

Mohs hardness is 5.5-6. Common colors include yellow.

Where is eltyubyuite found?+

Notable localities include Xenolith No.1, the Upper Chegem Caldera, Northern Caucasus, Kabardino-Balkaria and the Kel’ Plateau, Shadil-Khokh volcano, southern flank of the Greater Caucasian Mountain Range, Southern Ossetia, Russia; Eifel, Germany.

What rocks look like eltyubyuite?+

Eltyubyuite is most often confused with Sodalite, Haüyne, Lazurite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with eltyubyuite?+

Eltyubyuite commonly co-occurs with Larnite, Rondorfite, Wadalite, Hydroxylellestadite, Edgrewite-hydroxyledgrewite, Chegemite-fluorchegemite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does eltyubyuite form in?+

Where it forms: From a thermally-altered carbonate-silicate xenolith (20 m long) in ignimbrite that created sanidinite facies metamorphism (Upper Chegem Caldera). Working float back to the host body is the standard way to chase a fresh occurrence.

What is eltyubyuite used for?+

Eltyubyuite is used in collector.

Find eltyubyuite on the map

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