Putzite is an extremely rare silver-copper-germanium sulfide mineral typically found in epithermal vein deposits. Collectors should look for its metallic gray appearance in massive, granular forms within sulfidic ore samples, often identified through professional geochemical analysis.
Is this putzite?
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 putzite with a known reference. Putzite sits at Mohs 3-3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: black.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: iron black.
- 5Look at form & habitCrystal system: cubic. Typical habit: anhedral grains, granular.
Often confused with
Putzite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Putzite leaves black, Argyrodite leaves gray-black; luster reads metallic on Putzite and strong metallic on Argyrodite.
How to tell apart: Streak differs, so Putzite leaves black, Canfieldite leaves gray-black, somewhat shining.
Often found alongside putzite
Minerals reported to co-occur with putzite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Cu₈GeS₆
- Mohs hardness
- 3-3.5
- Density
- 5.778 g/cm³
- Colors
- Streak
- Black
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Cubic
- Crystal habit
- Anhedral grains, granular
- Cleavage
- One direction distinct in polished sections
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Fills cavities and vugs in bornite-chalcocite ore associated with andesitic rocks which host porphyry Cu-Au and epithermal vein-type mineral deposits
Where rockhounds find putzite
Classic worldwide localities
- Old dumps near the Rosario vein, Capillitas mining district, Department of Andalgalá, Catamarca Province, Argentina (type locality)
Field-hunting tip
Where it forms: Fills cavities and vugs in bornite-chalcocite ore associated with andesitic rocks which host porphyry Cu-Au and epithermal vein-type mineral deposits. If you start seeing catamarcaite, hübnerite, ge-stannoidite in float, you are in the right ground. Typical habit: anhedral grains, granular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify putzite?+
Where is putzite found?+
Is putzite safe to handle?+
What rocks look like putzite?+
What minerals are found with putzite?+
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What is putzite used for?+
Find putzite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
