Werdingite is a rare borosilicate mineral found primarily in high-grade metamorphic environments. It typically occurs as small, brownish prismatic crystals or granular masses embedded within granulite or khondalite rocks.

Hardness

7-7.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrare

Werdingite

Hardness: 7-7.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this werdingite?

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 werdingite with a known reference. Werdingite sits at Mohs 7-7.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Werdingite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Werdingite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: brown, tan, grayish-brown.
5
Look at form & habit
Crystal system: triclinic. Typical habit: prismatic crystals, granular aggregates.

Often confused with

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

Often found alongside werdingite

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

All properties

Chemical formula: (Mg,Fe)₂Al₈(Si,Al)₄O₂₂(OH,F)₂
Mohs hardness: 7-7.5
Density: 3.32 g/cm³
Colors: Brown Tan Grayish-brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Triclinic
Crystal habit: Prismatic Crystals, Granular Aggregates
Cleavage: Distinct
Rarity: Rare
Uses: Collector
Host rock: Metamorphic Rocks, Specifically Granulite-facies Terrains
Typical price: $50-300 per specimen

Where rockhounds find werdingite

Classic worldwide localities

Werding, Bavaria, Germany
Sri Lanka
Madagascar
Canada

Field-hunting tip

Look in metamorphic rocks, specifically granulite-facies terrains country — that is the host setting where werdingite typically forms. If you start seeing sillimanite, cordierite, garnet in float, you are in the right ground. Field specimens usually show a prismatic crystals, granular aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify werdingite?+

Mohs hardness is 7-7.5. It typically shows a vitreous luster. The streak is white. Common colors include brown, tan, grayish-brown.

Where is werdingite found?+

Notable localities include Werding, Bavaria, Germany; Sri Lanka; Madagascar; Canada.

How much is werdingite 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 werdingite?+

Werdingite is most often confused with Sillimanite, Andalusite, Kyanite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with werdingite?+

Werdingite commonly co-occurs with Sillimanite, Cordierite, Garnet, Quartz. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does werdingite form in?+

Werdingite typically forms in metamorphic rocks, specifically granulite-facies terrains. Working float back to the host body is the standard way to chase a fresh occurrence.

What is werdingite used for?+

Werdingite is used in collector.

Find werdingite on the map

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