Keldyshite is a rare sodium zirconium silicate primarily found in alkaline igneous environments like the Kola Peninsula. It is typically identified by its tabular or platy crystal habit and is often associated with other rare zirconium-bearing minerals in pegmatite pockets. Because of its rarity and resemblance to other alkaline silicates, it is highly prized by advanced mineral collectors.
Is this keldyshite?
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 keldyshite with a known reference. Keldyshite sits at Mohs 5-6 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Keldyshite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Keldyshite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: white, colorless, gray.
- 5Look at form & habitCrystal system: triclinic. Typical habit: platy crystals, tabular aggregates.
Often confused with
Keldyshite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside keldyshite
Minerals reported to co-occur with keldyshite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂ZrSi₂O₇
- Mohs hardness
- 5-6
- Density
- 2.85 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Triclinic
- Crystal habit
- Platy Crystals, Tabular Aggregates
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Alkaline Igneous Rocks, Specifically Pegmatites and Nepheline Syenites
- Typical price
- $50-300 per specimen depending on size and quality
Where rockhounds find keldyshite
Classic worldwide localities
- Khibiny Massif, Russia
- Lovozero Massif, Russia
- Mont Saint-Hilaire, Canada
Field-hunting tip
Look in alkaline igneous rocks, specifically pegmatites and nepheline syenites country — that is the host setting where keldyshite typically forms. If you start seeing aegirine, microcline, arfvedsonite in float, you are in the right ground. Field specimens usually show a platy crystals, tabular aggregates habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify keldyshite?+
Where is keldyshite found?+
How much is keldyshite worth?+
What rocks look like keldyshite?+
What minerals are found with keldyshite?+
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Find keldyshite on the map
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