Naldrettite is a very rare palladium antimonide discovered in the copper-nickel ores of the Sudbury Igneous Complex. It typically occurs as microscopic grains intergrown with other platinum-group minerals, making it a challenging find even for advanced collectors. It is named in honor of Anthony J. Naldrett, a prominent Canadian geologist specializing in magmatic sulfide deposits.
Is this naldrettite?
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 naldrettite with a known reference. Naldrettite sits at Mohs 4.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Naldrettite leaves a black streak.
- 3Read the lusterHold the specimen under a strong light. Naldrettite typically shows a metallic luster.
- 4Match the color rangeCompare against the expected color range: white, silver-white.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: anhedral grains.
Often confused with
Naldrettite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside naldrettite
Minerals reported to co-occur with naldrettite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Pd₂Sb
- Mohs hardness
- 4.5
- Density
- 9.64 g/cm³
- Colors
- Streak
- Black
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Orthorhombic
- Crystal habit
- Anhedral Grains
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Magmatic Sulfide Deposits
Where rockhounds find naldrettite
Classic worldwide localities
- Sudbury District, Ontario, Canada
Field-hunting tip
Look in magmatic sulfide deposits country, the host setting where naldrettite typically forms. If you start seeing sperrylite, kotulskite, michenerite 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 naldrettite?+
Where is naldrettite found?+
What rocks look like naldrettite?+
What minerals are found with naldrettite?+
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Find naldrettite on the map
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