Allendeite is a rare scandium-rich mineral found exclusively within the refractory inclusions of the Allende meteorite. It typically occurs as microscopic anhedral grains associated with other rare refractory minerals in extraterrestrial materials.

Hardness
5-6
Mohs
Transparency
Opaque

Is this allendeite?

2-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 allendeite with a known reference. Allendeite sits at Mohs 5-6, softer than the next harder reference, harder than the previous one.
  • 2
    Look at form & habit
    Crystal system: trigonal. Typical habit: inclusions, microscopic crystals.

Often confused with

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

Often found alongside allendeite

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

All properties

Chemical formula
Sc₄Zr₃O₁₂
Mohs hardness
5-6
Density
4.84 g/cm³
Transparency
Opaque
Crystal system
Trigonal
Crystal habit
Inclusions, microscopic crystals
Rarity
Rare
Uses
Collector
Host rock
As grains in an ovoid-shaped, ultra-refractory inclusion in the Allende meteorite, likely a high-temperature condensate early in the formation of the solar system

Where rockhounds find allendeite

Classic worldwide localities

  • Allende meteorite, Pueblito de Allende, Chihuahua, Mexico (type locality)

Field-hunting tip

Where it forms: As grains in an ovoid-shaped, ultra-refractory inclusion in the Allende meteorite, likely a high-temperature condensate early in the formation of the solar system. If you start seeing perovskite, os-ir-mo-w alloys, sc-stabilized tazheranite in float, you are in the right ground. Typical habit: inclusions, microscopic crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify allendeite?+
Mohs hardness is 5-6.
Where is allendeite found?+
Notable localities include Allende meteorite, Pueblito de Allende, Chihuahua, Mexico (type locality).
What rocks look like allendeite?+
Allendeite is most often confused with Thortveitite, Bazzite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with allendeite?+
Allendeite commonly co-occurs with Perovskite, Os-Ir-Mo-W alloys, Sc-stabilized tazheranite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does allendeite form in?+
Where it forms: As grains in an ovoid-shaped, ultra-refractory inclusion in the Allende meteorite, likely a high-temperature condensate early in the formation of the solar system. Working float back to the host body is the standard way to chase a fresh occurrence.
What is allendeite used for?+
Allendeite is used in collector.

Find allendeite on the map

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

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