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, so 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, 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.