Kamphaugite-(Y) is a rare yttrium-bearing carbonate mineral that typically occurs as thin, platy, pearl-like crystals. It is primarily found in complex rare-earth element (REE) environments associated with syenite pegmatites. Collectors generally look for its characteristic radial or rosette-like crystal clusters in hydrothermal vugs.

Hardness

2-3

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent to translucent

mineralrare

Kamphaugite-(Y)

Hardness: 2-3
Luster: Vitreous
Streak: White
Transparency: Transparent to translucent

Is this kamphaugite-(y)?

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 kamphaugite-(y) with a known reference. Kamphaugite-(Y) sits at Mohs 2-3, 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: white, brown, colorless, light yellow.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: spherical.

Often confused with

Kamphaugite-(Y) vs. its common look-alikes, and how to tell them apart in the field.

mineral

Bastnäsite

Mohs 4-5

How to tell apart: Bastnäsite is the harder of the two (Mohs 4-5 vs. 2-3).

Compare →

All properties

Chemical formula: CaY(CO₃)₂(OH)·H₂O
Mohs hardness: 2-3
Density: 3.19 g/cm³
Colors: White Brown Colorless Light yellow
Streak: White
Luster: Vitreous
Transparency: Transparent to translucent
Crystal system: Tetragonal
Crystal habit: Spherical
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: A late, low-temperature mineral formed in a contact-metamorphic skarn (Hørtekollen deposit, Norway); in metasomatically altered alkali granite (Kazakhstan)

Where rockhounds find kamphaugite-(y)

Classic worldwide localities

Gronci-Ellis granite quarry, Mount Desert, Hancock Co., Maine, USA
Hørtekollen deposit, Lier, Buskerud, Norway
Høydalen granite pegmatite, Tørdal, Telemark, Norway
Tangen granite pegmatite, near Kragerø, Norway
Cala Francese, Sardinia, Italy
Szarvaskő, Bükk Mountains, Hungary

Field-hunting tip

Where it forms: A late, low-temperature mineral formed in a contact-metamorphic skarn (Hørtekollen deposit, Norway); in metasomatically altered alkali granite (Kazakhstan). If you start seeing kuliokite-, gagarinite, kainosite- in float, you are in the right ground. Typical habit: spherical. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kamphaugite-(y)?+

Mohs hardness is 2-3. Luster: vitreous. The streak is white. Common colors include white, brown, colorless, light yellow.

Where is kamphaugite-(y) found?+

Notable localities include Gronci-Ellis granite quarry, Mount Desert, Hancock Co., Maine, USA; Hørtekollen deposit, Lier, Buskerud, Norway; Høydalen granite pegmatite, Tørdal, Telemark, Norway; Tangen granite pegmatite, near Kragerø, Norway; Cala Francese, Sardinia, Italy.

What rocks look like kamphaugite-(y)?+

Kamphaugite-(Y) is most often confused with Bastnäsite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with kamphaugite-(y)?+

Kamphaugite-(Y) commonly co-occurs with Kuliokite-, Gagarinite, Kainosite-, Hingganite-, Caysichite-, Donnayite-. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does kamphaugite-(y) form in?+

Where it forms: A late, low-temperature mineral formed in a contact-metamorphic skarn (Hørtekollen deposit, Norway); in metasomatically altered alkali granite (Kazakhstan). Working float back to the host body is the standard way to chase a fresh occurrence.

What is kamphaugite-(y) used for?+

Kamphaugite-(Y) is used in collector.

Find kamphaugite-(y) on the map

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