Hydroxynatropyrochlore is a rare member of the pyrochlore group characterized by its sodium and hydroxyl content within the structural formula. It typically forms sharp, octahedral crystals in alkaline rock environments such as carbonatites and syenites, often appearing in shades of brown or yellow.
Is this hydroxynatropyrochlore?
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 hydroxynatropyrochlore with a known reference. Hydroxynatropyrochlore 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: adamantine to greasy.
- 4Match the color rangeCompare against the expected color range: pale brown.
- 5Look at form & habitCrystal system: cubic. Typical habit: octahedral crystals.
Often confused with
Hydroxynatropyrochlore vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Hydroxynatropyrochlore leaves white, Pyrochlore leaves brown; luster reads adamantine to greasy on Hydroxynatropyrochlore and vitreous to resinous on Pyrochlore.
How to tell apart: Zircon is the harder of the two (Mohs 7.5 vs. ~5); luster reads adamantine to greasy on Hydroxynatropyrochlore and vitreous to adamantine; greasy when metamict on Zircon.
Often found alongside hydroxynatropyrochlore
Minerals reported to co-occur with hydroxynatropyrochlore. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Na,Ca,Ce)₂Nb₂O₆(OH)
- Mohs hardness
- ~5
- Density
- 4.2-4.8 g/cm³
- Colors
- Streak
- White
- Luster
- Adamantine to greasy
- Transparency
- Transparent to translucent
- Crystal system
- Cubic
- Crystal habit
- Octahedral crystals
- Cleavage
- Average on {111}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- alkaline igneous rocks
Where rockhounds find hydroxynatropyrochlore
Classic worldwide localities
- Kovdor phoscorite-carbonatite pipe, Kola Peninsula, Russia
Field-hunting tip
Where it forms: alkaline igneous rocks. If you start seeing calcite, dolomite, forsterite in float, you are in the right ground. Typical habit: octahedral crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hydroxynatropyrochlore?+
Where is hydroxynatropyrochlore found?+
Is hydroxynatropyrochlore safe to handle?+
What rocks look like hydroxynatropyrochlore?+
What minerals are found with hydroxynatropyrochlore?+
What kind of rock does hydroxynatropyrochlore form in?+
What is hydroxynatropyrochlore used for?+
Find hydroxynatropyrochlore on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
