Ellenbergerite is an extremely rare silicate mineral found in ultra-high-pressure metamorphic rocks. It typically occurs as small, pale pink or colorless prismatic crystals, primarily recognized from its type locality in the Dora-Maira massif of Italy.

Hardness

6.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Ellenbergerite

Hardness: 6.5
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this ellenbergerite?

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 ellenbergerite with a known reference. Ellenbergerite sits at Mohs 6.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: colorless, purple, lilac.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: hexagonal prismatic crystals.

Often confused with

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

How to tell apart: Phenakite is the harder of the two (Mohs 7.5-8 vs. 6.5).

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Often found alongside ellenbergerite

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

All properties

Chemical formula: Mg₆(Mg,Ti,Zr,□)₂(Al,Mg)₆Si₈O₂₈(OH)₁₀
Mohs hardness: 6.5
Density: 3.15-3.22 g/cm³
Colors: Colorless PurpleLilac
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Hexagonal
Crystal habit: Hexagonal prismatic crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: As inclusions in pyrope porphyroblasts developed during high-pressure (25–30 kbar), medium-temperature (700 ° C{800 ° C) metamorphism of continental crustal rocks

Where rockhounds find ellenbergerite

Classic worldwide localities

Dora-Maira massif, Parigi, near Martiniana Po, Piedmont, Italy

Field-hunting tip

Where it forms: As inclusions in pyrope porphyroblasts developed during high-pressure (25–30 kbar), medium-temperature (700 ° C{800 ° C) metamorphism of continental crustal rocks. If you start seeing pyrope, kyanite, talc in float, you are in the right ground. Typical habit: hexagonal prismatic crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ellenbergerite?+

Mohs hardness is 6.5. Luster: vitreous. The streak is white. Common colors include colorless, purple, lilac.

Where is ellenbergerite found?+

Notable localities include Dora-Maira massif, Parigi, near Martiniana Po, Piedmont, Italy.

What rocks look like ellenbergerite?+

Ellenbergerite is most often confused with Quartz, Phenakite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with ellenbergerite?+

Ellenbergerite commonly co-occurs with Pyrope, Kyanite, Talc, Clinochlore, Rutile, Zircon. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does ellenbergerite form in?+

Where it forms: As inclusions in pyrope porphyroblasts developed during high-pressure (25–30 kbar), medium-temperature (700 ° C{800 ° C) metamorphism of continental crustal rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ellenbergerite used for?+

Ellenbergerite is used in collector.

Find ellenbergerite on the map

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