Addibischoffite is a rare calcium aluminum oxide that forms an irregular mass. It was approved as a distinct mineral species in 2015. It was first described from material found in Algeria (meteorite).

Hardness

7-7.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareGarnet Group family

Addibischoffite

Hardness: 7-7.5
Luster: Vitreous
Streak: White
Transparency: Translucent

No image

Is this addibischoffite?

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 addibischoffite with a known reference. Addibischoffite sits at Mohs 7-7.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Addibischoffite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Addibischoffite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: deep red, brownish-red.
5
Look at form & habit
Crystal system: triclinic. Typical habit: an irregular mass.

Often confused with

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

mineral

Almandine

Mohs 7-7.5

How to tell apart: Luster reads vitreous on Addibischoffite and vitreous to subresinous on Almandine.

Often found alongside addibischoffite

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

All properties

Chemical formula: Ca₂(Al,Mg,V,Ti)₆(Al,Si)₆O₂₀
Mohs hardness: 7-7.5
Density: 3.41 g/cm³
Colors: Deep Red Brownish-red
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Triclinic
Crystal habit: An Irregular Mass
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Metamorphic Rocks

Where rockhounds find addibischoffite

Classic worldwide localities

Western Australia
Antarctica

Field-hunting tip

Look in metamorphic rocks country, the host setting where addibischoffite typically forms. If you start seeing quartz, mica, feldspar in float, you are in the right ground. Field specimens usually show a an irregular mass habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify addibischoffite?+

Mohs hardness is 7-7.5. It typically shows a vitreous luster. The streak is white. Common colors include deep red, brownish-red.

Where is addibischoffite found?+

Notable localities include Western Australia; Antarctica.

What rocks look like addibischoffite?+

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

What minerals are found with addibischoffite?+

Addibischoffite commonly co-occurs with Quartz, Mica, Feldspar. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does addibischoffite form in?+

Addibischoffite typically forms in metamorphic rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is addibischoffite used for?+

Addibischoffite is used in collector.

Find addibischoffite on the map

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