Yuanjiangite is an extremely rare gold-tin intermetallic mineral typically found as microscopic inclusions within larger gold or sulfide masses. It was first identified in the Yuanjiang area of China and requires advanced geological analysis for positive field identification due to its scarcity and minute crystal size.

Hardness

3.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Yuanjiangite

Hardness: 3.5
Luster: Metallic
Streak: Black
Transparency: Opaque

No image

Is this yuanjiangite?

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 yuanjiangite with a known reference. Yuanjiangite sits at Mohs 3.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Yuanjiangite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Yuanjiangite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: white, silver-white.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: microscopic grains and inclusions.

Often confused with

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

mineral

Gold

Mohs 2.5-3

How to tell apart: Streak differs — Yuanjiangite leaves black, Gold leaves golden yellow.

Often found alongside yuanjiangite

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

All properties

Chemical formula: AuSn
Mohs hardness: 3.5
Density: 9.9 g/cm³
Colors: White Silver-white
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Hexagonal
Crystal habit: Microscopic Grains and Inclusions
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Veins in Tin-gold Deposits
Typical price: n/a

Where rockhounds find yuanjiangite

Classic worldwide localities

Yuanjiang, China
Kola Peninsula, Russia

Field-hunting tip

Look in hydrothermal veins in tin-gold deposits country — that is the host setting where yuanjiangite typically forms. If you start seeing gold, galena, chalcopyrite in float, you are in the right ground. Field specimens usually show a microscopic grains and inclusions habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify yuanjiangite?+

Mohs hardness is 3.5. It typically shows a metallic luster. The streak is black. Common colors include white, silver-white.

Where is yuanjiangite found?+

Notable localities include Yuanjiang, China; Kola Peninsula, Russia.

How much is yuanjiangite worth?+

Typical asking prices fall in the range of n/a. Quality, size, and provenance can move individual specimens well outside that range.

Is yuanjiangite safe to handle?+

It contains toxic constituents. Contains tin and gold in a metallic state, but dust inhalation should be avoided as it is often associated with other heavy metal minerals in complex ore deposits. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like yuanjiangite?+

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

What minerals are found with yuanjiangite?+

Yuanjiangite commonly co-occurs with gold, galena, chalcopyrite, pyrite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does yuanjiangite form in?+

Yuanjiangite typically forms in hydrothermal veins in tin-gold deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is yuanjiangite used for?+

Yuanjiangite is used in collector.

Find yuanjiangite on the map

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