Skaergaardite
Chemical formula: PdCu
Skaergaardite is a very rare, natural alloy of palladium and copper, discovered in the famous Skaergaard intrusion in Greenland.
Properties
- Mohs hardness
- 5
- Luster
- Metallic
- Streak
- Gray
- Density
- 10.96
- Cleavage
- None
- Fracture
- Uneven
- Transparency
- Opaque
- Crystal system
- Cubic
Diagnostic features
## Identification Identification of skaergaardite is impossible without advanced laboratory equipment. Recognition is based on optical analysis in reflected light (characteristic color and high reflectivity) and chemical analysis using an electron microprobe (EDS/WDS) to confirm its composition (palladium and copper). ## Distinguishing from Similar Minerals Under the microscope, it can be confused with other platinum-group minerals (PGM) or metal alloys, such as hongshiite (PtCu) or tetraferroplatinum (PtFe). Definitive differentiation requires quantitative chemical composition analysis. ## Crystal Forms Skaergaardite occurs as anhedral (irregularly shaped), rounded grains or interstitial fillings. No well-formed, euhedral crystal forms have been observed.
Geological environment
## Genesis Skaergaardite crystallizes in the late stages of basaltic magma solidification, under conditions of strong magmatic differentiation. It forms as a result of the concentration of palladium and copper in the final, residual magmatic liquid that fills the spaces between earlier crystallized silicates. ## Mineral Associations This mineral occurs in paragenesis with other platinum-group minerals, sulfides, and metal alloys. It is most commonly associated with: chalcopyrite, bornite, digenite, ilmenite, magnetite, native gold, as well as other rare minerals such as wassonite, keithconnite, or zvyagintsevite. It also co-occurs with rock-forming silicates, such as plagioclase and pyroxenes. ## Localities The type and main locality where this mineral was identified is the Skaergaard intrusion in Greenland. Its occurrence has also been confirmed in the Fedorovo-Pansky magmatic complex on the Kola Peninsula in Russia and in the Rincón del Tigre intrusion in Bolivia.
Rarity
Extremely rare
For collectors
## Quality Criteria The quality of skaergaardite specimens is assessed solely in a scientific and micromount context. The most highly valued specimens are those in which skaergaardite grains are as large as possible (though still microscopic), numerous, and occur in interesting paragenesis with other rare minerals. The quality of the petrographic thin section preparation and accurate analytical documentation confirming the mineral's presence are also crucial. ## Market Prices Skaergaardite practically does not appear on the commercial collector's market. Specimens are mainly found in the collections of scientific institutions and museums. Any potential transactions would occur in a highly specialized market and would likely involve entire petrographic thin sections, with their price being difficult to estimate and dependent on the uniqueness of the research material. ## Popular Localities The only source of specimens that could hypothetically enter advanced collections is the Skaergaard intrusion in Greenland.
Care and storage
## Cleaning Skaergaardite specimens typically occur as polished petrographic thin sections or as inclusions in the host rock, invisible to the naked eye. For this reason, cleaning in the traditional sense is neither necessary nor possible. Polished sections can only be wiped with a soft, dry microfiber cloth to remove dust or fingerprints. ## What to Avoid Avoid any chemicals, acids, solvents, and ultrasonic cleaners. Contact with chemicals can irreversibly damage both the mineral itself and the epoxy resin in which sections are often embedded. Protect specimens from scratching and impacts. ## Storage Petrographic thin sections or small fragments of host rock are best stored in dedicated membrane boxes or padded collector boxes to protect their delicate, polished surface. Avoid exposure to moisture and extreme temperatures.