Parakeldyshite is a rare sodium zirconium silicate mineral typically found in complex alkaline igneous rocks. Collectors primarily seek it from the classic pegmatite localities of the Kola Peninsula and Mont Saint-Hilaire, where it occurs as small, glassy tabular crystals.
Is this parakeldyshite?
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 parakeldyshite with a known reference. Parakeldyshite sits at Mohs 5.5-6, 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: bluish white, white.
- 5Look at form & habitCrystal system: triclinic. Typical habit: tabular crystals, massive, granular.
Often confused with
Parakeldyshite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside parakeldyshite
Minerals reported to co-occur with parakeldyshite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂ZrSi₂O₇
- Mohs hardness
- 5.5-6
- Density
- 3.37-3.39 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Triclinic
- Crystal habit
- Tabular crystals, massive, granular
- Cleavage
- Perfect on {001}; very good on {110} and {110}; good on {011}
- Fluorescence
- Orange-white under SW UV
- Rarity
- Rare
- Uses
- Collector, Research
- Host rock
- As masses in nepheline syenite pegmatites which cut a foyaite (Bratthagen, Norway)
Where rockhounds find parakeldyshite
Classic worldwide localities
- Mt. Takhtarvumchorr, in the Khibiny massif, and on Mt. Alluaiv, in the Lovozero massif, Kola Peninsula, Russia
- Bratthagen, near Larvik, Norway
- Mont Saint-Hilaire, Quebec, Canada
Field-hunting tip
Where it forms: As masses in nepheline syenite pegmatites which cut a foyaite (Bratthagen, Norway). If you start seeing alkalic feldspar, nepheline, aegirine in float, you are in the right ground. Typical habit: tabular crystals, massive, granular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify parakeldyshite?+
Where is parakeldyshite found?+
What rocks look like parakeldyshite?+
What minerals are found with parakeldyshite?+
What kind of rock does parakeldyshite form in?+
What is parakeldyshite used for?+
Find parakeldyshite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
