Penzhinite is a rare silver-gold-copper sulfosalt mineral primarily identified from epithermal deposits in the Russian Far East. It typically occurs as microscopic anhedral grains intergrown with other precious metal minerals, requiring microscopic analysis for positive identification.

Hardness

2.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrareMiner Group family

Penzhinite

Hardness: 2.5
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this penzhinite?

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 penzhinite with a known reference. Penzhinite sits at Mohs 2.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Penzhinite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Penzhinite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: silver-white, pale yellow.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: anhedral grains.

Often confused with

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

Often found alongside penzhinite

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

All properties

Chemical formula: (Ag,Cu)₇(Au,Ag)S₄
Mohs hardness: 2.5
Density: 9.5-9.8 g/cm³
Colors: Silver-white Pale Yellow
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Orthorhombic
Crystal habit: Anhedral Grains
Cleavage: None
Rarity: Rare
Uses: Collector, Scientific Research
Host rock: Epithermal Gold-silver Deposits
Typical price: $100-500 per specimen

Where rockhounds find penzhinite

Classic worldwide localities

Penzhina River, Kamchatka, Russia

Field-hunting tip

Look in epithermal gold-silver deposits country — that is the host setting where penzhinite typically forms. If you start seeing petrovskaite, gold, acanthite in float, you are in the right ground. Field specimens usually show a anhedral grains habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify penzhinite?+

Mohs hardness is 2.5. It typically shows a metallic luster. The streak is black. Common colors include silver-white, pale yellow.

Where is penzhinite found?+

Notable localities include Penzhina River, Kamchatka, Russia.

How much is penzhinite worth?+

Typical asking prices fall in the range of $100-500 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

Is penzhinite safe to handle?+

It contains toxic constituents. Contains silver and copper, but specifically significant concentrations of heavy metals; handle with care and wash hands after contact. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like penzhinite?+

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

What minerals are found with penzhinite?+

Penzhinite commonly co-occurs with Petrovskaite, Gold, Acanthite, Quartz. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does penzhinite form in?+

Penzhinite typically forms in epithermal gold-silver deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is penzhinite used for?+

Penzhinite is used in collector, scientific research.

Find penzhinite on the map

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