Sopcheite is a rare silver-palladium telluride mineral discovered in the layered intrusions of the Kola Peninsula. It is typically found as microscopic inclusions within copper-nickel sulfide ores and is highly valued by specialized collectors of platinum-group minerals.
Is this sopcheite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch sopcheite with a known reference. Sopcheite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: grayish-black.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: brownish gray.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: microscopic crystals.
Often confused with
Sopcheite vs. its common look-alikes, and how to tell them apart in the field.

How to tell apart: Sopcheite is noticeably harder (Mohs 3.5 vs. 1.5-2); streak differs, so Sopcheite leaves grayish-black, Tellurobismuthite leaves pale lead-gray.

How to tell apart: Streak differs, so Sopcheite leaves grayish-black, Hessite leaves light gray.

How to tell apart: Streak differs, so Sopcheite leaves grayish-black, Kotulskite leaves black.
Often found alongside sopcheite
Minerals reported to co-occur with sopcheite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ag₄Pd₃Te₄
- Mohs hardness
- 3.5
- Density
- 9.948 g/cm³
- Colors
- Streak
- Grayish-black
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Orthorhombic
- Crystal habit
- Microscopic crystals
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In veinlets cutting chalcopyrite (Monchegorsk deposits, Russia)
Where rockhounds find sopcheite
Classic worldwide localities
- Monchegorsk group of Cu–Ni deposits, in the Sopcha massif, Monchegorsk pluton, Kola Peninsula, Russia (type locality)
- Roby zone, Lac des Iles complex, Ontario, Canada
- Levack West mine, Sudbury, Ontario, Canada
- Geordie Lake intrusion, Coldwell complex, Ontario, Canada
- Santo Tomas II porphyry copper deposit, Benguet, Philippines
Field-hunting tip
Where it forms: In veinlets cutting chalcopyrite (Monchegorsk deposits, Russia). If you start seeing merenskyite, kotulskite, chalcopyrite in float, you are in the right ground. Typical habit: microscopic crystals. Train your eye for that shape before scanning the outcrop.


