Hydroxyplumbopyrochlore is a rare lead-dominant member of the pyrochlore supergroup found in evolved alkaline pegmatites. It typically occurs as distinct, resinous octahedral crystals that are often dark brown or yellowish-brown in color. Collectors prize these for their complexity and rarity, though they require careful handling due to lead content and radioactivity.

Hardness

5-5.5

Mohs

Luster

Resinous

Streak

Light Yellow

Transparency

Translucent

mineralrarePyrochlore Supergroup family

Hydroxyplumbopyrochlore

Hardness: 5-5.5
Luster: Resinous
Streak: Light Yellow
Transparency: Translucent

No image

Is this hydroxyplumbopyrochlore?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch hydroxyplumbopyrochlore with a known reference. Hydroxyplumbopyrochlore sits at Mohs 5-5.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Hydroxyplumbopyrochlore leaves a light yellow streak.
3
Read the luster
Hold the specimen under a strong light. Hydroxyplumbopyrochlore typically shows a resinous luster.
4
Match the color range
Compare against the expected color range: yellowish-brown, brown, reddish-brown.
5
Look at form & habit
Crystal system: cubic. Typical habit: octahedral crystals.

Often found alongside hydroxyplumbopyrochlore

Minerals reported to co-occur with hydroxyplumbopyrochlore. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: (Pb,Y,U,Ca)₂(Nb,Ta,Ti)₂O₆(OH)
Mohs hardness: 5-5.5
Density: 5.6-6.1 g/cm³
Colors: Yellowish-brown Brown Reddish-brown
Streak: Light Yellow
Luster: Resinous
Transparency: Translucent
Crystal system: Cubic
Crystal habit: Octahedral Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Alkaline Pegmatites
Typical price: $50-300 per small specimen

Where rockhounds find hydroxyplumbopyrochlore

Classic worldwide localities

Kola Peninsula, Russia
Langesundsfjord, Norway

Field-hunting tip

Look in alkaline pegmatites country, the host setting where hydroxyplumbopyrochlore typically forms. If you start seeing zircon, aegirine, microcline in float, you are in the right ground. Field specimens usually show a octahedral crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify hydroxyplumbopyrochlore?+

Mohs hardness is 5-5.5. It typically shows a resinous luster. The streak is light yellow. Common colors include yellowish-brown, brown, reddish-brown.

Where is hydroxyplumbopyrochlore found?+

Notable localities include Kola Peninsula, Russia; Langesundsfjord, Norway.

How much is hydroxyplumbopyrochlore worth?+

Typical asking prices fall in the range of $50-300 per small specimen. Quality, size, and provenance can move individual specimens well outside that range.

Is hydroxyplumbopyrochlore safe to handle?+

This mineral is radioactive. It contains toxic constituents. Contains lead and is radioactive; handle with care, avoid creating dust, and store away from other minerals to prevent radioactive damage to sensitive specimens. Handle with care, avoid grinding or breathing dust, and store separately.

What minerals are found with hydroxyplumbopyrochlore?+

Hydroxyplumbopyrochlore commonly co-occurs with Zircon, Aegirine, Microcline, Nepheline. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does hydroxyplumbopyrochlore form in?+

Hydroxyplumbopyrochlore typically forms in alkaline pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is hydroxyplumbopyrochlore used for?+

Hydroxyplumbopyrochlore is used in collector.

Find hydroxyplumbopyrochlore on the map

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