Fengchengite is a rare iron-aluminum garnet variety primarily identified in specific metamorphic terranes in China. It typically forms characteristic dodecahedral crystals and is highly prized by collectors for its distinct chemistry and provenance. It is often found associated with silicate minerals in high-grade metamorphic rock environments.

Hardness

6.5-7.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareGarnet Group family

Fengchengite

Hardness: 6.5-7.5
Luster: Vitreous
Streak: White
Transparency: Translucent

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Is this fengchengite?

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 fengchengite with a known reference. Fengchengite sits at Mohs 6.5-7.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Fengchengite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Fengchengite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, reddish-brown.
5
Look at form & habit
Crystal system: cubic. Typical habit: dodecahedral crystals, granular.

Often confused with

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

Often found alongside fengchengite

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

All properties

Chemical formula: Fe₃Al₂Si₃O₁₂
Mohs hardness: 6.5-7.5
Density: 3.5-3.8 g/cm³
Colors: Yellow Brown Reddish-brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Cubic
Crystal habit: Dodecahedral Crystals, Granular
Cleavage: None
Rarity: Rare
Uses: Collector, Scientific Research
Host rock: Metamorphic Rocks
Typical price: $50-500 depending on specimen quality

Where rockhounds find fengchengite

Classic worldwide localities

Fengcheng, Liaoning Province, China

Field-hunting tip

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

Common questions

How do you identify fengchengite?+

Mohs hardness is 6.5-7.5. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown, reddish-brown.

Where is fengchengite found?+

Notable localities include Fengcheng, Liaoning Province, China.

How much is fengchengite worth?+

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

What rocks look like fengchengite?+

Fengchengite is most often confused with Almandite, Spessartine. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with fengchengite?+

Fengchengite commonly co-occurs with Quartz, Feldspar, Mica. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does fengchengite form in?+

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

What is fengchengite used for?+

Fengchengite is used in collector, scientific research.

Find fengchengite on the map

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