Kristiansenite is a rare calcium scandium tin silicate. It was approved as a distinct mineral species in 2000, from material found at Heftetjern, Tørdal, Telemark, Norway.

Hardness

5.5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrare

Kristiansenite

Kristiansenite is a rare calcium scandium tin silicate. It was approved as a distinct mineral species in 2000, from material found at Heftetjern, Tørdal, Telemark, Norway.

Hardness: 5.5-6
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this kristiansenite?

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 kristiansenite with a known reference. Kristiansenite sits at Mohs 5.5-6, 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: triclinic. Typical habit: striated, tabular, tapered.

Often confused with

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

Often found alongside kristiansenite

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

All properties

Chemical formula: Ca₄Sc₂Sn₂(Si₂O₇)₂(Si₂O₆OH)₂
Mohs hardness: 5.5-6
Density: 3.3 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Triclinic
Crystal habit: Striated, tabular, tapered
Cleavage: Perfect in one direction
Rarity: Rare
Uses: Collector
Host rock: Late-stage hydrothermal mineral in a granite pegmatite

Where rockhounds find kristiansenite

Classic worldwide localities

Heftejern, Tørdal, Telemark, Norway (type locality)

Field-hunting tip

Where it forms: Late-stage hydrothermal mineral in a granite pegmatite. If you start seeing albite, aegirine, microcline in float, you are in the right ground. Typical habit: striated, tabular, tapered. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify kristiansenite?+

Mohs hardness is 5.5-6. Luster: vitreous. The streak is white. Common colors include colorless, white.

Where is kristiansenite found?+

Notable localities include Heftejern, Tørdal, Telemark, Norway (type locality).

What rocks look like kristiansenite?+

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

What minerals are found with kristiansenite?+

Kristiansenite commonly co-occurs with Albite, Aegirine, Microcline, Zircon, Astrophyllite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does kristiansenite form in?+

Where it forms: Late-stage hydrothermal mineral in a granite pegmatite. Working float back to the host body is the standard way to chase a fresh occurrence.

What is kristiansenite used for?+

Kristiansenite is used in collector.

Find kristiansenite on the map

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