Hydroxycalciopyrochlore is a rare member of the pyrochlore group often found in alkaline igneous environments like carbonatites. It typically occurs as small, well-formed octahedral crystals that are often radioactive due to trace elements like uranium and thorium.

Hardness

5-5.5

Mohs

Luster

Vitreous

Streak

Light Yellow

Transparency

Translucent

mineralrarePyrochlore Group family

Hydroxycalciopyrochlore

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

No image

Is this hydroxycalciopyrochlore?

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 hydroxycalciopyrochlore with a known reference. Hydroxycalciopyrochlore 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. Hydroxycalciopyrochlore leaves a light yellow streak.
3
Read the luster
Hold the specimen under a strong light. Hydroxycalciopyrochlore typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, reddish-brown.
5
Look at form & habit
Crystal system: cubic. Typical habit: octahedral crystals.

Often found alongside hydroxycalciopyrochlore

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

All properties

Chemical formula: (Ca,Na,U)₂(Nb,Ti,Ta)₂(O,OH)₇(OH,F)
Mohs hardness: 5-5.5
Density: 4.2-6.4 g/cm³
Colors: Yellow Brown Reddish-brown
Streak: Light Yellow
Luster: Vitreous
Transparency: Translucent
Crystal system: Cubic
Crystal habit: Octahedral Crystals
Cleavage: None
Rarity: Rare
Uses: Collector, Scientific Research
Host rock: Carbonatites
Typical price: $50-500 depending on crystal size and quality

Where rockhounds find hydroxycalciopyrochlore

Classic worldwide localities

Fen Complex, Norway
Kola Peninsula, Russia
Oka Carbonatite, Canada

Field-hunting tip

Look in carbonatites country, the host setting where hydroxycalciopyrochlore typically forms. If you start seeing calcite, apatite, biotite 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 hydroxycalciopyrochlore?+

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

Where is hydroxycalciopyrochlore found?+

Notable localities include Fen Complex, Norway; Kola Peninsula, Russia; Oka Carbonatite, Canada.

How much is hydroxycalciopyrochlore worth?+

Typical asking prices fall in the range of $50-500 depending on crystal size and quality. Quality, size, and provenance can move individual specimens well outside that range.

Is hydroxycalciopyrochlore safe to handle?+

This mineral is radioactive. Contains uranium and thorium; store in a shielded container and avoid inhalation of dust when handling samples. Handle with care, avoid grinding or breathing dust, and store separately.

What minerals are found with hydroxycalciopyrochlore?+

Hydroxycalciopyrochlore commonly co-occurs with Calcite, Apatite, Biotite, Magnetite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does hydroxycalciopyrochlore form in?+

Hydroxycalciopyrochlore typically forms in carbonatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is hydroxycalciopyrochlore used for?+

Hydroxycalciopyrochlore is used in collector, scientific research.

Find hydroxycalciopyrochlore on the map

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