Cabriite
Chemical formula: Pd<sub>2</sub>CuSn
Cabriite is a rare, metallic mineral from the native elements group, being a natural alloy of palladium, copper, and tin.
Properties
- Mohs hardness
- 4
- Luster
- Metallic
- Streak
- Grey
- Density
- 10.95
- Cleavage
- None
- Fracture
- Uneven
- Transparency
- Opaque
- Crystal system
- Cubic
Diagnostic features
## Identification Identifying cabriite is extremely difficult and impossible without specialized equipment. It requires advanced methods such as chemical composition analysis using an electron microprobe (EDS/WDS) and crystal structure analysis by X-ray diffraction (XRD). Under a polarizing microscope in reflected light, it exhibits a creamy-white color with a pinkish hue and is isotropic. ## Distinguishing from Similar Minerals Cabriite can be confused with other rare platinum-group minerals (PGM) such as taimanite, stannopalladinite, or atokite, which have a similar appearance and co-occur in the same deposits. Definitive differentiation is only possible based on precise chemical analysis. ## Crystal Forms Cabriite crystallizes in the isometric system. Most often, it forms irregular, rounded grains and aggregates. Very rarely, poorly developed, small crystals in the form of cubes or octahedra are observed.
Geological environment
## Genesis Cabriite is a mineral of magmatic origin. It forms in ultramafic and mafic magmatic intrusions, during the crystallization process from magma rich in sulfides, copper, nickel, and platinum-group elements (PGE). ## Mineral Associations This mineral occurs in association with other ore minerals, especially sulfides and platinum-group metals. It most commonly co-occurs with chalcopyrite, talnakhite, cubanite, magnetite, taimanite, stannopalladinite, polarite, mayakite, atokite, rustenburgite, native gold, and sperrylite. ## Localities The most important and well-documented cabriite localities worldwide are: - Russia: Oktyabr'skoye copper-nickel deposit (type locality) and Talnakh deposit in the Norilsk region of Siberia. - Canada: Sudbury mine in Ontario and Lac-des-Îles deposit. - South Africa: Bushveld Igneous Complex, particularly in the Onverwacht and Mooihoek deposits.
Rarity
Very rare
For collectors
## Quality Criteria The quality of cabriite specimens, from a collector's and scientific perspective, depends almost exclusively on the size and degree of development of the grains or crystals. Since this mineral is extremely rare and occurs as microscopic inclusions, any visually identifiable (even under a microscope) and well-documented specimen is valuable. The most desirable specimens are those with visible, even if small, well-formed crystals or rich aggregates in the host rock, originating from the type locality (Norilsk). ## Popular Localities The most prized and classic cabriite specimens come from the copper-nickel deposits in the Norilsk region of Siberia (Russia), where this mineral was first discovered and described.
Care and storage
## Cleaning Due to its extreme rarity and small grain size, cabriite specimens are typically not cleaned. If they are on a stable matrix, it can be gently dusted with a soft brush. ## What to Avoid Avoid contact with any chemicals, acids, and cleaning agents. Do not subject it to ultrasonic cleaning or sudden temperature changes. As a soft mineral, it is susceptible to scratching. ## Storage Cabriite specimens, usually in the form of microscopic grains within the host rock, should be stored in stable conditions, in a closed display box, to protect them from dust and mechanical damage. Avoid direct sunlight and humidity.