Matioliite is a rare phosphate mineral found in complex granite pegmatites. It typically occurs as small, sharp, bipyramidal crystals that can be transparent to translucent, often found associated with other phosphate minerals.
Is this matioliite?
5-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 matioliite with a known reference. Matioliite sits at Mohs ~5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: blue, colorless.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic, tabular.
Often confused with
Matioliite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside matioliite
Minerals reported to co-occur with matioliite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaMgAl₅(PO₄)₄(OH)₆·2H₂O
- Mohs hardness
- ~5
- Density
- 2.948 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic, tabular
- Cleavage
- Perfect on {100}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A secondary hydrothermal mineral in granite pegmatite
Where rockhounds find matioliite
Classic worldwide localities
- Gentil mine, Mendes Pimentel County, Minas Gerais, Brazil (type locality)
Field-hunting tip
Where it forms: A secondary hydrothermal mineral in granite pegmatite. If you start seeing fluorapatite, crandallite, zoned gormanite-souzalite crystals in float, you are in the right ground. Typical habit: prismatic, tabular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify matioliite?+
Where is matioliite found?+
What rocks look like matioliite?+
What minerals are found with matioliite?+
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What is matioliite used for?+
Find matioliite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
