Silesiaite is a rare iron-rich member of the garnet group historically described from the Silesia region. It typically appears as yellowish to brown dodecahedral crystals formed in metamorphic environments and is highly sought after by systematic mineral collectors.

Hardness

6.5-7

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareGarnet Group family

Silesiaite

Hardness: 6.5-7
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this silesiaite?

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 silesiaite with a known reference. Silesiaite sits at Mohs 6.5-7 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Silesiaite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Silesiaite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, greenish.
5
Look at form & habit
Crystal system: isometric. Typical habit: dodecahedral crystals.

Often confused with

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

Often found alongside silesiaite

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

All properties

Chemical formula: Ca₃Fe³⁺₂Si₃O₁₂
Mohs hardness: 6.5-7
Density: 3.5-3.6 g/cm³
Colors: Yellow Brown Greenish
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Isometric
Crystal habit: Dodecahedral Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Metamorphic Rocks
Typical price: $50-500 depending on specimen size and clarity

Where rockhounds find silesiaite

Classic worldwide localities

Silesia
Poland
Czech Republic

Field-hunting tip

Look in metamorphic rocks country — that is the host setting where silesiaite typically forms. If you start seeing quartz, epidote, calcite in float, you are in the right ground. Field specimens usually show a dodecahedral crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify silesiaite?+

Mohs hardness is 6.5-7. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown, greenish.

Where is silesiaite found?+

Notable localities include Silesia; Poland; Czech Republic.

How much is silesiaite worth?+

Typical asking prices fall in the range of $50-500 depending on specimen size and clarity. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like silesiaite?+

Silesiaite is most often confused with Andradite, Grossularite Garnet. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with silesiaite?+

Silesiaite commonly co-occurs with Quartz, Epidote, Calcite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does silesiaite form in?+

Silesiaite typically forms in metamorphic rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is silesiaite used for?+

Silesiaite is used in collector.

Find silesiaite on the map

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