Hydroxycancrinite is a relatively rare silicate mineral that typically forms as an alteration product of nepheline in alkaline igneous environments. It is best identified by its distinct hexagonal crystal structure and strong fluorescence under ultraviolet light, appearing as white to yellowish massive or prismatic aggregates.
Is this hydroxycancrinite?
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 hydroxycancrinite with a known reference. Hydroxycancrinite sits at Mohs 6, 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: light blue, colorless.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: massive, prismatic crystals.
Often confused with
Hydroxycancrinite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside hydroxycancrinite
Minerals reported to co-occur with hydroxycancrinite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Na,Ca,K)₈(Al₆Si₆O₂₄)(OH,CO₃)₂·2H₂O
- Mohs hardness
- 6
- Density
- 2.32 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Hexagonal
- Crystal habit
- Massive, prismatic crystals
- Cleavage
- Perfect on {1010}
- Fluorescence
- Bright yellow or orange under UV
- Rarity
- Rare
- Uses
- Collector, Mineralogical study
- Host rock
- In veins in ultra-agpaitic pegmatites in a differentiated alkalic massif
Where rockhounds find hydroxycancrinite
Classic worldwide localities
- Mt. Karnasurt, Lovozero massif, Kola Peninsula, Russia
Field-hunting tip
Where it forms: In veins in ultra-agpaitic pegmatites in a differentiated alkalic massif. If you start seeing natrolite, steenstrupine, vuonnemite in float, you are in the right ground. Typical habit: massive, prismatic crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hydroxycancrinite?+
Where is hydroxycancrinite found?+
What rocks look like hydroxycancrinite?+
What minerals are found with hydroxycancrinite?+
What kind of rock does hydroxycancrinite form in?+
What is hydroxycancrinite used for?+
Find hydroxycancrinite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
