[meteorite-list] Fusion Crust

[MstrEman]

In the totally "for what its worth" category...

As to what the crust might be like chemically , I'll have to think it
through more but what comes to mind first is instead of much magnetite
( Iron Oxide: Fe3O4)) which gives OCs that velvet look, one might find
the variations on the nickel iron carbides and carbonates.  Probably
very little carbonate because it tends to decompose at earthly reentry
temperature.  Magnetite  it seems is formed but gets recycled.  Iron
Carbide has a graphite-like metallic color.

"The thermal decomposition of carbon dioxide has been investigated
behind reflected shock waves at temperatures of 3200–4600K  and
pressures of 45–100kPa "
BUT
"The CO2 decomposition occurs in two steps at temperatures near 773 K:
First wustite (FeO) reacts with CO2 to form carbon monxide (CO) and
magnetite (Fe3O4); then CO disproportionates to C(gr) and CO2. Fe3O4
can be recycled to Fe1-yO by thermal dissociation above 2200 K... "


Iron minerals: iron carbide (cementite) or iron carbonate (siderite)
nickel minerals  nickle carbide (cohenite) and nickle carbonate (zaratite)

The Nickel-Iron intermediary minerals  ferro-nickel  carbide(Haxonite
)   ferro-nickel magnesium carbonate ( Gaspeite).  All of the carbides
have been found in meteorites already.  The carbonates probably many
have been after terrestrial alteration on earth.


Like was said would be really insightful if we were able to take stock
of a meteorite's crust on the surface of Mars.
Elton