Platinum
Platinum (element #78, symbol Pt) is a dense, silvery-gray metal. The platinum group of elements consists of metals with similar physical properties to platinum and these elements are among the rarest in the Earth’s crust. They have high melting points, are dense or heavy and are non-reactive with other elements. The platinum group metals (PGM) include ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir) and platinum. Of these elements, only platinum and palladium are found in a pure form in nature. The others occur in nature as natural alloys with platinum and gold, for example.
Type
Element (Minerals/Ores of)
Mineral Classification
Native element
Chemical Formula
Pt
Streak
grayish white
Mohs Hardness
4-4.5
Crystal System
Isometric
Color
Dark gray, steel gray, whitish gray
Luster
Metallic
Fracture
Jagged
Description
Platinum (element #78, symbol Pt) is a dense, silvery-gray metal. The platinum group of elements consists of metals with similar physical properties to platinum and these elements are among the rarest in the Earth’s crust. They have high melting points, are dense or heavy and are non-reactive with other elements. The platinum group metals (PGM) include ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir) and platinum. Of these elements, only platinum and palladium are found in a pure form in nature. The others occur in nature as natural alloys with platinum and gold, for example.
Uses
Platinum is used principally as catalysts for the control of automobile and industrial plant emissions (such as in catalytic converters), as catalysts to produce acids, organic chemicals, and pharmaceuticals. Platinum group metals are used in bushings for making glass fibers used in fiber-reinforced plastic and other advanced materials, in electrical contacts, capacitors, conductive and resistive films used in electronic circuits, dental alloys used for making crowns and bridges, and jewelry.