Tschermakite is a complex calcium-magnesium-aluminum silicate belonging to the amphibole group, typically found in high-grade metamorphic rocks. Collectors often identify it by its prismatic, dark-colored crystalline habit and its occurrence within metamorphic terrains like skarns and amphibolites.

Hardness

5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineraluncommonAmphibole Group family

Tschermakite

Hardness: 5-6
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this tschermakite?

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 tschermakite with a known reference. Tschermakite sits at Mohs 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. Tschermakite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Tschermakite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: black, dark green, dark brown.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: prismatic crystals, massive, granular.

Often confused with

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

mineral

Hornblende

Mohs 5-6

How to tell apart: Streak differs — Tschermakite leaves white, Hornblende leaves grayish-white.

Often found alongside tschermakite

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

All properties

Chemical formula: Ca₂(Mg₃Al₂)(Si₆Al₂)O₂₂(OH)₂
Mohs hardness: 5-6
Density: 3.2-3.5 g/cm³
Colors: Black Dark Green Dark Brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Prismatic Crystals, Massive, Granular
Cleavage: Perfect in Two Directions
Rarity: Uncommon
Uses: Collector, Petrological Studies
Host rock: Metamorphic Rocks Like Amphibolites and Skarns
Typical price: $10-50 per specimen

Where rockhounds find tschermakite

Classic worldwide localities

Tschermak, Austria
Adirondack Mountains, USA
Grenville Province, Canada
Kola Peninsula, Russia

Field-hunting tip

Look in metamorphic rocks like amphibolites and skarns country — that is the host setting where tschermakite typically forms. If you start seeing garnet, diopside, plagioclase in float, you are in the right ground. Field specimens usually show a prismatic crystals, massive, granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify tschermakite?+

Mohs hardness is 5-6. It typically shows a vitreous luster. The streak is white. Common colors include black, dark green, dark brown.

Where is tschermakite found?+

Notable localities include Tschermak, Austria; Adirondack Mountains, USA; Grenville Province, Canada; Kola Peninsula, Russia.

How much is tschermakite worth?+

Typical asking prices fall in the range of $10-50 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like tschermakite?+

Tschermakite is most often confused with Hornblende, Edenite, Pargasite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with tschermakite?+

Tschermakite commonly co-occurs with Garnet, Diopside, Plagioclase, Quartz. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does tschermakite form in?+

Tschermakite typically forms in metamorphic rocks like amphibolites and skarns. Working float back to the host body is the standard way to chase a fresh occurrence.

What is tschermakite used for?+

Tschermakite is used in collector, petrological studies.

Find tschermakite on the map

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