Tveitite-(Y) is a rare yttrium-calcium fluoride mineral found primarily in granitic pegmatites. It is highly prized by collectors for its distinctive bright white fluorescence under short-wave ultraviolet light, which helps differentiate it from common fluorite.

Hardness
3.5
Mohs
Luster
Vitreous
Streak
White
Transparency
Translucent

Is this tveitite-(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 tveitite-(y) with a known reference. Tveitite-(Y) sits at Mohs 3.5 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Tveitite-(Y) leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Tveitite-(Y) typically shows a vitreous luster.
  • 4
    Match the color range
    Compare against the expected color range: white, colorless, yellowish-white.
  • 5
    Look at form & habit
    Crystal system: trigonal. Typical habit: rhombohedral crystals, massive.

Often confused with

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

Often found alongside tveitite-(y)

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

All properties

Chemical formula
(Y,Ca)₅(F,O)₁₁
Mohs hardness
3.5
Density
3.45 g/cm³
Streak
White
Luster
Vitreous
Transparency
Translucent
Crystal system
Trigonal
Crystal habit
Rhombohedral Crystals, Massive
Cleavage
None
Fluorescence
Bright White/pale Yellow Under SW UV
Rarity
Rare
Uses
Collector
Host rock
Granite Pegmatites
Typical price
$50-300 per specimen

Where rockhounds find tveitite-(y)

Classic worldwide localities

  • Tveitdalen, Iveland, Norway
  • Hittero, Norway

Field-hunting tip

Look in granite pegmatites country — that is the host setting where tveitite-(y) typically forms. If you start seeing fluorite, quartz, microcline in float, you are in the right ground. Field specimens usually show a rhombohedral crystals, massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify tveitite-(y)?+
Mohs hardness is 3.5. It typically shows a vitreous luster. The streak is white. Common colors include white, colorless, yellowish-white.
Where is tveitite-(y) found?+
Notable localities include Tveitdalen, Iveland, Norway; Hittero, Norway.
How much is tveitite-(y) worth?+
Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.
What rocks look like tveitite-(y)?+
Tveitite-(Y) is most often confused with Fluorite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with tveitite-(y)?+
Tveitite-(Y) commonly co-occurs with Fluorite, Quartz, Microcline, Albite, Allanite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does tveitite-(y) form in?+
Tveitite-(Y) typically forms in granite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.
What is tveitite-(y) used for?+
Tveitite-(Y) is used in collector.

Find tveitite-(y) on the map

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

Download on the App StoreGet it on Google Play