Presolar Silicon Carbide (SiC) Grains
Image: <a href="//commons.wikimedia.org/wiki/User:Warrenmck" title="User:Warrenmck">Warrenmck</a> (CC BY-SA 4.0)
Mineral NamePresolar Silicon Carbide (SiC) Grains
Chemical FormulaSiC
Mohs Hardness9
Streak Colorgreenish-black/gray
Cleavagepoor/indistinct
Fractureconchoidal/uneven
Specific Gravity3.21
Colorsblack, gray, greenish-black
Transparencyopaque
Type LocalityOrgueil meteorite (extraterrestrial, AGB star origin)
Mineral GroupCarbides
Usesscientific research, cosmochemistry studies
Associated Mineralspresolar graphite, presolar nanodiamonds, presolar oxides, presolar silicates
Rarityvery-rare
Description
The image displays a small vial held in a hand, containing a clear liquid with numerous tiny, dark, particulate grains suspended, which are presolar silicon carbide.
Geological Context
These grains are extraterrestrial, formed in the stellar outflows of evolved stars (like AGB stars) prior to the formation of our solar system, and were subsequently preserved within primitive meteorites such as the Orgueil meteorite.
