Quadridavyne is a rare member of the cancrinite group found primarily within volcanic ejecta of the Somma-Vesuvius region. Collectors typically identify it through its characteristic tetragonal prismatic crystal habit, which distinguishes it from the more common hexagonal davyne.
Is this quadridavyne?
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 quadridavyne with a known reference. Quadridavyne 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: colorless.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: hexagonal, prismatic.
Often confused with
Quadridavyne vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside quadridavyne
Minerals reported to co-occur with quadridavyne. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- [(Na,K)₆Cl₂][Ca₂Cl₂][(Si₆Al₆O₂₄)]
- Mohs hardness
- ~5
- Density
- 2.335 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Hexagonal
- Crystal habit
- Hexagonal, prismatic
- Cleavage
- {0001}, perfect; {1120}, distinct
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In volcanic ash containing metasomatized and hydrothermally altered lavas and scoriae, from the 1906 eruption of Vesuvius
Where rockhounds find quadridavyne
Classic worldwide localities
- Ottaviano, near Naples, Campania, Italy
Field-hunting tip
Where it forms: In volcanic ash containing metasomatized and hydrothermally altered lavas and scoriae, from the 1906 eruption of Vesuvius. If you start seeing nepheline, sanidine, phlogopite in float, you are in the right ground. Typical habit: hexagonal, prismatic. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify quadridavyne?+
Where is quadridavyne found?+
What rocks look like quadridavyne?+
What minerals are found with quadridavyne?+
What kind of rock does quadridavyne form in?+
What is quadridavyne used for?+
Find quadridavyne on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
