Harstigite is a very rare sorosilicate mineral primarily known from the historic manganese mines of Värmland, Sweden. It typically occurs as small, pale, prismatic crystals within metamorphosed carbonate-rich environments associated with manganese ores.

Hardness

5.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent to translucent

mineralrare

Harstigite

Hardness: 5.5
Luster: Vitreous
Streak: White
Transparency: Transparent to translucent

Is this harstigite?

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 harstigite with a known reference. Harstigite sits at Mohs 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. 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, colorless.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: crystalline, prismatic.

Often confused with

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

mineral

Epidote

Mohs 6-7

How to tell apart: Streak differs, so Harstigite leaves white, Epidote leaves grayish white.

Compare →

Often found alongside harstigite

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

All properties

Chemical formula: Ca₆MnBe₄(SiO₄)₂(Si₂O₇)₂(OH)₂
Mohs hardness: 5.5
Density: 3.16 g/cm³
Colors: White Colorless
Streak: White
Luster: Vitreous
Transparency: Transparent to translucent
Crystal system: Orthorhombic
Crystal habit: Crystalline, prismatic
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: A rare mineral found in open fissures in a metamorphosed manganese deposit

Where rockhounds find harstigite

Classic worldwide localities

Harstigen mine, near Persberg, Värmland, Sweden

Field-hunting tip

Where it forms: A rare mineral found in open fissures in a metamorphosed manganese deposit. If you start seeing hausmannite, dolomite, calcite in float, you are in the right ground. Typical habit: crystalline, prismatic. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify harstigite?+

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

Where is harstigite found?+

Notable localities include Harstigen mine, near Persberg, Värmland, Sweden.

Is harstigite safe to handle?+

Harstigite contains beryllium. Wash your hands afterwards, never grind or breathe the dust, and store it apart from specimens you handle often.

What rocks look like harstigite?+

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

What minerals are found with harstigite?+

Harstigite commonly co-occurs with Hausmannite, Dolomite, Calcite, Rhodonite, Andradite, Manganoan humite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does harstigite form in?+

Where it forms: A rare mineral found in open fissures in a metamorphosed manganese deposit. Working float back to the host body is the standard way to chase a fresh occurrence.

What is harstigite used for?+

Harstigite is used in collector.

Find harstigite on the map

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