Nielsenite is a rare palladium-copper intermetallic mineral usually found as microscopic grains in complex magmatic sulfide deposits. It is best identified through reflected light microscopy or microprobe analysis rather than traditional hand-specimen inspection. Collectors generally encounter it only within specialized suites of platinum-group minerals from major layered intrusions.
Is this nielsenite?
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 nielsenite with a known reference. Nielsenite 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: black.
- 3Read the lusterHold the specimen under a strong light. Luster: metallic.
- 4Match the color rangeCompare against the expected color range: steel gray.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: anhedral grains.
Often confused with
Nielsenite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Nielsenite leaves black, Gold leaves yellow.
How to tell apart: Streak differs, so Nielsenite leaves black, Platinum leaves grayish white.
How to tell apart: Palladium is the harder of the two (Mohs 4.5-5 vs. 3.5); streak differs, so Nielsenite leaves black, Palladium leaves silver-white.
Often found alongside nielsenite
Minerals reported to co-occur with nielsenite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- PdCu₃
- Mohs hardness
- 3.5
- Density
- 9.53 g/cm³
- Colors
- Streak
- Black
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Tetragonal
- Crystal habit
- Anhedral grains
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- As the crystallized products of immiscible melts in thoelitic gabbro and that formed at temperatures at of below 508° C, in a highly differentiated layered intrusion
Where rockhounds find nielsenite
Classic worldwide localities
- Platinova Reef, Skaergaard intrusion, Kangerdlunssuaq area, East Greenland
Field-hunting tip
Where it forms: As the crystallized products of immiscible melts in thoelitic gabbro and that formed at temperatures at of below 508° C, in a highly differentiated layered intrusion. If you start seeing bornite-chalcocite, skaergaardite, keithconnite in float, you are in the right ground. Typical habit: anhedral grains. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify nielsenite?+
Where is nielsenite found?+
Is nielsenite safe to handle?+
What rocks look like nielsenite?+
What minerals are found with nielsenite?+
What kind of rock does nielsenite form in?+
What is nielsenite used for?+
Find nielsenite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
