Fluorcalciopyrochlore is a rare member of the pyrochlore group characterized by its dominant calcium and fluorine content. It typically forms octahedral crystals in carbonatites and alkaline igneous rocks, often exhibiting brownish hues and radioactive properties due to potential uranium impurities.

Hardness

5-5.5

Mohs

Luster

Vitreous

Streak

Light Yellow

Transparency

Translucent

mineralrarePyrochlore Group family

Fluorcalciopyrochlore

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

Is this fluorcalciopyrochlore?

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

Often confused with

Fluorcalciopyrochlore vs. its common look-alikes — and how to tell them apart in the field.

mineral

Zircon

Mohs 7.5

How to tell apart: Zircon is the harder of the two (Mohs 7.5 vs. 5-5.5); streak differs — Fluorcalciopyrochlore leaves light yellow, Zircon leaves white; luster reads vitreous on Fluorcalciopyrochlore and adamantine on Zircon.

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Often found alongside fluorcalciopyrochlore

Minerals reported to co-occur with fluorcalciopyrochlore. 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)₂O₆(F,OH)
Mohs hardness: 5-5.5
Density: 4.2-4.8 g/cm³
Colors: Brown Yellowish-brown Reddish-brown Black
Streak: Light Yellow
Luster: Vitreous
Transparency: Translucent
Crystal system: Cubic
Crystal habit: Octahedral Crystals, Massive, Granular
Cleavage: None
Rarity: Rare
Uses: Collector, Scientific Study
Host rock: Carbonatites, Alkaline Igneous Rocks
Typical price: $20-150 for thumbnail to small cabinet specimens depending on crystal definition.

Where rockhounds find fluorcalciopyrochlore

Classic worldwide localities

Kaiserstuhl, Germany
Fen Complex, Norway
Kola Peninsula, Russia
Oka, Canada

Field-hunting tip

Look in carbonatites, alkaline igneous rocks country — that is the host setting where fluorcalciopyrochlore typically forms. If you start seeing calcite, apatite, nepheline in float, you are in the right ground. Field specimens usually show a octahedral crystals, massive, granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify fluorcalciopyrochlore?+

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

Where is fluorcalciopyrochlore found?+

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

How much is fluorcalciopyrochlore worth?+

Typical asking prices fall in the range of $20-150 for thumbnail to small cabinet specimens depending on crystal definition.. Quality, size, and provenance can move individual specimens well outside that range.

Is fluorcalciopyrochlore safe to handle?+

This mineral is radioactive. Due to its radioactivity, this mineral should be stored in a shielded container away from other mineral specimens and handled with caution, avoiding the inhalation of dust or ingestion. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like fluorcalciopyrochlore?+

Fluorcalciopyrochlore is most often confused with Zircon. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with fluorcalciopyrochlore?+

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

What kind of rock does fluorcalciopyrochlore form in?+

Fluorcalciopyrochlore typically forms in carbonatites, alkaline igneous rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is fluorcalciopyrochlore used for?+

Fluorcalciopyrochlore is used in collector, scientific study.

Find fluorcalciopyrochlore on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.