Nacaphite is a rare phosphate mineral primarily found in hyper-alkaline igneous complexes. It usually occurs as colorless or pale yellow grains and tabular crystals embedded within nepheline-rich environments.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Nacaphite

Hardness: 3
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this nacaphite?

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 nacaphite with a known reference. Nacaphite sits at Mohs 3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: colorless, white.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals, massive, granular.

Often confused with

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

mineral

Apatite

Mohs 5

How to tell apart: Apatite is the harder of the two (Mohs 5 vs. 3).

Often found alongside nacaphite

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

All properties

Chemical formula: Na₂CaPO₄F
Mohs hardness: 3
Density: 2.85 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Tabular crystals, massive, granular
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: A rare late-stage hydrothermal mineral in ijolite-urtite pegmatite

Where rockhounds find nacaphite

Classic worldwide localities

Mts. Rasvumchorr, Yukspor, and Koashva, Khibiny massif, Kola Peninsula, Russia

Field-hunting tip

Where it forms: A rare late-stage hydrothermal mineral in ijolite-urtite pegmatite. If you start seeing thermonatrite, villiaumite, aegirine in float, you are in the right ground. Typical habit: tabular crystals, massive, granular. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify nacaphite?+

Mohs hardness is 3. Luster: vitreous. The streak is white. Common colors include colorless, white.

Where is nacaphite found?+

Notable localities include Mts. Rasvumchorr, Yukspor, and Koashva, Khibiny massif, Kola Peninsula, Russia.

What rocks look like nacaphite?+

Nacaphite is most often confused with Apatite, Villiaumite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with nacaphite?+

Nacaphite commonly co-occurs with Thermonatrite, Villiaumite, Aegirine, Apatite, Barytolamprophyllite, Interstial with nepheline. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does nacaphite form in?+

Where it forms: A rare late-stage hydrothermal mineral in ijolite-urtite pegmatite. Working float back to the host body is the standard way to chase a fresh occurrence.

What is nacaphite used for?+

Nacaphite is used in collector.

Find nacaphite on the map

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