Mineral - Platinum
Platinum
Chemical Properties
Mineral Class
Elements
Toxicity
none
Formula
Pt
Unit Cell
a=3.92 Z=4
Physical Properties
Hardness
3.5
Streak
whitegraygray white
Density
Very Heavy (>6)
Cleavage
Fracture
hooked
Tenacity
Supple
Optical Properties
Color
graygray whitesilver
Birefringence
Luster
Metallic
Transparency
opaque
Pleochroism
Geomineralogical Properties
Crystal System
isometric
Point Group
hexoctahedral - 4/m 3 2/m
Space Group
Fm 3 m (225)
Habit
coarse, dodecahedron, bulbous, granular, skeletal, Cube
Formation
(1) Primarily magmatic, formed by fractional crystallization and gravitational separation as a sulfide melt in mafic to ultramafic intrusions.
(2) Secondary, as a fluvial placer deposit due to its high chemical resistance and density during weathering
Paragenesis
Twinning
Rarity
Very rare
Synonyms
Platinum
Composition
Elements
Mass
Pt
86.20
Ir
0.85
Os
0.95
Rh
1.40
Pd
0.50
Au
1.00
Cu
0.60
Fe
7.80
Colombia (Palache et al. 1952)