Maghrebite is an extremely rare magnesium arsenate mineral first described from the Tounfit region of Morocco. It typically appears as small, colorless prismatic crystals and is primarily a prize for advanced mineralogists focusing on rare arsenates.
Is this maghrebite?
4-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch maghrebite with a known reference. Maghrebite sits at Mohs >2, softer than the next harder reference, harder than the previous one.
- 2Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 3Match the color rangeCompare against the expected color range: colorless.
- 4Look at form & habitCrystal system: triclinic. Typical habit: prismatic to acicular crystals.
Often found alongside maghrebite
Minerals reported to co-occur with maghrebite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- MgAl₂(AsO₄)₂(OH)₂(H₂O)₆·2H₂O
- Mohs hardness
- >2
- Density
- 2.60 g/cm³
- Colors
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Triclinic
- Crystal habit
- Prismatic to acicular crystals
- Cleavage
- Perfect on {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- From weathering Co-arsenides in a hydrothermal Co-Ni-As-(Cu-U-Mo) vein in an arid environment
Where rockhounds find maghrebite
Classic worldwide localities
- Aghbar mine, Bou Azzer district, Anti-Atlas, Morocco
Field-hunting tip
Where it forms: From weathering Co-arsenides in a hydrothermal Co-Ni-As-(Cu-U-Mo) vein in an arid environment. If you start seeing erythrite, wendwilsonite, arseniosiderite in float, you are in the right ground. Typical habit: prismatic to acicular crystals. Train your eye for that shape before scanning the outcrop.





