Matteuccite is a rare sulfate mineral typically found as a volcanic sublimated product in fumarole vents. Collectors should look for delicate, needle-like white or colorless crystals forming crusts; it is highly water-soluble and must be stored in a dry environment.
Is this matteuccite?
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 matteuccite with a known reference. Matteuccite sits at Mohs 2, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Matteuccite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Matteuccite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: acicular or fibrous crystals, often as crusts or efflorescences.
Often confused with
Matteuccite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside matteuccite
Minerals reported to co-occur with matteuccite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaHSO₄·H₂O
- Mohs hardness
- 2
- Density
- 2.12 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Acicular or Fibrous Crystals, Often as Crusts or Efflorescences
- Cleavage
- Good On {110}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Fumaroles
Where rockhounds find matteuccite
Classic worldwide localities
- Vesuvius, Italy
- Etna, Italy
- Tolbachik volcano, Russia
Field-hunting tip
Look in fumaroles country, the host setting where matteuccite typically forms. If you start seeing thenardite, gypsum, alums in float, you are in the right ground. Field specimens usually show a acicular or fibrous crystals, often as crusts or efflorescences habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify matteuccite?+
Where is matteuccite found?+
What rocks look like matteuccite?+
What minerals are found with matteuccite?+
What kind of rock does matteuccite form in?+
What is matteuccite used for?+
Find matteuccite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
