Ellingsenite is a rare mineral belonging to the apophyllite group, typically occurring as thin platy crystals. It is primarily identified in vugs within nepheline syenite pegmatites in the Larvik region of Norway. Collectors value it for its limited occurrence and specific crystalline association with other zeolites and related silicates.
Is this ellingsenite?
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 ellingsenite with a known reference. Ellingsenite sits at Mohs 4, 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 individuals, silky aggregates.
- 4Match the color rangeCompare against the expected color range: colorless, white in aggregates.
- 5Look at form & habitCrystal system: triclinic. Typical habit: platy crystals.
Often confused with
Ellingsenite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside ellingsenite
Minerals reported to co-occur with ellingsenite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₅Ca₆Si₁₈O₃₈(OH)₁₃·6H₂O
- Mohs hardness
- 4
- Density
- 2.32 g/cm³
- Colors
- ColorlessWhite in aggregates
- Streak
- White
- Luster
- Vitreous individuals, silky aggregates
- Transparency
- Transparent
- Crystal system
- Triclinic
- Crystal habit
- Platy crystals
- Cleavage
- Perfect on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A low-temperature mineral in vesicles in hydrothermally altered phonolite
Where rockhounds find ellingsenite
Classic worldwide localities
- Ariskop quarry, Aris alkaline complex, 25 km south of Windhoek, Namibia
Field-hunting tip
Where it forms: A low-temperature mineral in vesicles in hydrothermally altered phonolite. If you start seeing aegirine, albite, manganoneptunite in float, you are in the right ground. Typical habit: platy crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify ellingsenite?+
Where is ellingsenite found?+
What rocks look like ellingsenite?+
What minerals are found with ellingsenite?+
What kind of rock does ellingsenite form in?+
What is ellingsenite used for?+
Find ellingsenite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
